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Abstract: In this study, in order to obtain a wearable infrared‐transparent material based on nanoporous polyethylene, a newly ultrahigh molecular weight polyethylene (UHMWPE)/polyester composite fabric with nanoporous structure is developed via thermally induced phase separation (TIPS) method. A polyester mesh with loose warp/weft weaves is chosen as the intermediate to enhance the fabric mechanical strength and air permeability. Meanwhile, methoxy‐poly(ethylene glycol)‐aminoethyl/polydopamine particles (mPPDAPs) are used to improve the hydrophilicity of UHMWPE. The fabric is composited with mPPDAPs/UHMWPE/liquid paraffin mixture at high temperature. Then the nanoporous structure is formed via TIPS in UHMWPE phase in the composite fabric. This newly UHMWPE/polyester composite fabric possesses a unique connective nanoporous structure with the pore sizes distributed from 50 to 100 nm and it also has many disconnected honeycomb pores that are ≈1000 nm in diameter. These characteristics endow the composite fabric with excellent properties of wearability and optical properties, including sufficient moisture wicking rate, air permeability, and mechanical strength, high infrared‐transparent and ultraviolet/visible‐opaque properties. It is an effective, economical, and practical novel composite textile for human body cooling. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) porous membranes are fabricated via thermally induced phase separation (TIPS) with mixed diluent (dibutyl phthalate (DBP)/dioctyl phthalate (DOP)). The effects of mixed diluent are discussed in detail in term of morphology, mean pore size, selective wettability, etc. The results show that the membrane structure changes from spherulitic to bicontinuous with the change of DBP/DOP ratio. It is also found that the degree of crystallization decreases with the decrease of DBP/DOP ratio in mixed diluent. When liquid--liquid (L-L) phase separation precedes solid--liquid (S-L) phase separation, the obtained membranes have outstanding hydrophobicity and lipophilicity, excellent mechanical property. Additionally, the PVDF-HFP hybrid membranes are prepared with silica (SiO2) particles and the effect of SiO2 content on structure and properties is discussed. It is found that the PVDF-HFP hybrid membrane with 2 wt % SiO2 (M3-S2) has better properties and higher filtration rate and separation efficiency for surfactant-stabilized water-in-oil emulsion separation. Moreover, the membrane M3-S2 also exhibits excellent antifouling performance for long-running. [ABSTRACT FROM AUTHOR]

Growing attention given to non-toxic solvents for membrane preparation has been the motivation for membrane scientists to develop future generation membranes due to increasing concerns for environmental impacts and strict rules. In this study, a novel preparation approach for polypropylene (PP) membranes via TIPS using non-toxic binary diluents consisting of carnauba wax as latent solvent and soybean oil as good solvent was developed successfully. Water and ethanol were used as a quenching bath and extractant of diluents in the membrane, respectively. Impacts of both polymer weight fraction and carnauba wax weight fraction on the phase diagram (phase separation behaviors) of the PP/binary diluents system were investigated firstly. The liquid-liquid (L-L) phase separation region can be enlarged with the continuously increasing of carnauba wax. The effect of adding the second latent diluent on the structures and properties of PP membranes was also studied. The morphology of membranes was further controlled by adjusting the composition of binary diluents. The inter-connected spongelike structure was achieved successfully, which greatly increased the membrane elongation at break. Moreover, vacuum membrane distillation (VMD) desalination experiments showed that the PP membranes produced have the potentiality in VMD desalination application. The carnauba wax after extraction by boiling ethanol could be easily crystallized, separated and recycled by cooling. [ABSTRACT FROM AUTHOR]

Polycaprolactone (PCL) foams were produced by thermally induced phase separation. Tetrahydrofuran/methanol (THF/MeOH) (solvent/non-solvent) mixture was used for the induction of liquid-liquid phase separation of PCL solutions at three different temperatures. Subsequent solvent exchange followed by vacuum drying yielded polymeric foams with different morphologies. Characterization of foams was obtained by scanning electron microscopy, x-ray diffractometry, mercury intrusion porosimetry and compression tests. Influence of polymer concentration (8, 10 and 12 wt%), quench temperature (4, −20 and −80 °C), and THF/MeOH ratio from (42/58) to (54/46) (wt/wt) on the foam formation, morphology and properties were investigated systematically. Lower PCL concentration, lower THF content and higher quench temperature lead to larger pore sizes in the foams obtained. Detailed discussions of the influence of processing parameters on foam structure and porosity, foam density, percent crystallinity and compressive properties are provided. By selectively tuning the process parameters, foams with controlled pore sizes (10–450 μm), porosity (83–91%) and morphology (cellular, bead-like, microspherical) were obtained. [ABSTRACT FROM AUTHOR]

An experimental full phase diagram for the binary system low-density polyethylene – thymol was for the first time constructed in a broad temperature-concentration range using an original optical method, turbidimetry, and differential scanning calorimetry. Limitations of the two latter techniques were critically analyzed. The diagram belongs to the type semicrystalline polymer – thermodynamically poor solvent so that in the whole concentration range polyethylene and thymol play the role of a solvent and solute, respectively. Thermally induced phase separation leads to the formation of a capillary-porous body. Thymol crystals formed in its pores melt at lower temperatures than crystals from pure thymol solution. The data obtained by different methods can be used for developing the technology of fabricating films with antimicrobial properties. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA), dicalcium phosphate dihydrate (DCPD) and/or hydraulic calcium silicate (CaSi) have been used to prepare highly-porous scaffolds by thermally induced phase separation technique (TIPS). Three experimental mineral-doped formulations were prepared (PLA-10CaSi, PLA-5CaSi-5DCPD, PLA-10CaSi-10DCPD). Pure PLA scaffolds constituted the control group. Scaffolds were tested for their chemical-physical and biological properties, namely calcium release, alkalinizing activity, surface microchemistry and micromorphology by ESEM, apatite-forming ability by EDX, micro-Raman and IR spectroscopy, thermal properties by differential scanning calorimetry, mechanical properties by quasi-static parallel-plates compression testing, porosity by a standard water-absorption method and direct-contact cytotoxicity. All mineral-doped scaffolds released biologically relevant ions (biointeractive). A B-type carbonated apatite layer (thickness decreasing along the series PLA-10CaSi-10DCPD > PLA-10CaSi > PLA-5CaSi-5DCPD > PLA) was detected on the surface of all the 28d-aged scaffolds. Surface pores of fresh scaffolds ranged from 10 to 20 μm in pure PLA to 10–100 μm in PLA-10CaSi. An increase in porosity was detected in 28d–aged pure PLA scaffolds (approx. 30% of material loss with decrease of the PLA chain length); differently, in mineral-doped scaffolds, the PLA degradation was balanced by deposition/nucleation of apatite. All scaffolds showed absence of toxicity, in particular PLA-10CaSi-10DCPD. The designed scaffolds are biointeractive (release biologically relevant ions), nucleate apatite, possess high surface and internal open porosity and can be colonized by cells, appearing interesting materials for bone regeneration. [ABSTRACT FROM AUTHOR]

The solidification behavior of poly(vinylidene fluoride) (PVDF) solution during membrane preparation by thermally induced phase separation (TIPS) was investigated. Apparatus newly developed in our laboratory was used to quantitatively measure membrane stiffness during phase separation. In this apparatus, a cooling polymer solution, placed on a stage, is moved upwards and the surface of the polymer solution contacts a sphere attached to the tip of a needle. The displacement of a blade spring attached to the needle is then measured by a laser displacement sensor. Different phase separation modes, such as liquid-liquid (L-L) phase separation and solid-liquid (S-L) phase separation (polymer crystallization) were investigated. In the case of S-L phase separation, the stiffness of the solution surface began to increase significantly just before termination of crystallization. In contrast, L-L phase separation delayed solidification of the solution. This was because mutual contact of the spherulites was obstructed by droplets of polymer-lean phase formed during L-L phase separation. Thus, the solidification rate was slower for the L-L phase separation system than for the S-L phase separation system.

The spread of antibiotic-resistant pathogens requires new treatments. Small molecule precursor compounds that produce oxidative biocides with well-established antimicrobial properties could provide a range of new therapeutic products to combat resistant infections. The aim of this study was to investigate a novel biomaterials-based approach for the manufacture, targeted delivery and controlled release of a peroxygen donor (sodium percarbonate) combined with an acetyl donor (tetraacetylethylenediamine) to deliver local antimicrobial activity via a dynamic equilibrium mixture of hydrogen peroxide and peracetic acid. Entrapment of the pre-cursor compounds into hierarchically structured degradable microparticles was achieved using an innovative dry manufacturing process involving thermally induced phase separation (TIPS) that circumvented compound decomposition associated with conventional microparticle manufacture. The microparticles provided controlled release of hydrogen peroxide and peracetic acid that led to rapid and sustained killing of multiple drug-resistant organisms (methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli) without associated cytotoxicity in vitro nor intracutaneous reactivity in vivo . The results from this study demonstrate for the first time that microparticles loaded with acetyl and peroxygen donors retain their antimicrobial activity whilst eliciting no host toxicity. In doing so, it overcomes the detrimental effects that have prevented oxidative biocides from being used as alternatives to conventional antibiotics. Statement of Significance The manuscript explores a novel approach to utilize the antimicrobial activity of oxidative species for sustained killing of multiple drug-resistant organisms without causing collateral tissue damage. The results demonstrate, for the first time, the ability to load pre-cursor compounds into porous polymeric structures that results in their release and conversion into oxidative species in a controlled manner. Until now, the use of oxidative species has not been considered as a candidate therapeutic replacement for conventional antibiotics due to difficulties associated with handling during manufacture and controlling sustained release without causing undesirable tissue damage. The ultimate impact of the research could be the creation of new materials-based anti-infective chemotherapeutic agents that have minimal potential for giving rise to antimicrobial resistance. [ABSTRACT FROM AUTHOR]

A simple strategy of thermally induced phase separation followed by non-solvent induced phase separation (TIPS-NIPS) is reported to fabricate poly (vinylidene fluoride) (PVDF)-based blend membrane. The dissolved poly (styrene-co-maleic anhydride) (SMA) in diluent prevents the crystallization of PVDF during the cooling process and deposites on the established PVDF matrix in the later extraction. Compared with traditional coating technique, this one-step TIPS-NIPS method can not only fabricate a supporting layer with an interconnected network structure even via solid-liquid phase separation of TIPS, but also form a uniform SMA skin layer approximately as thin as 200 nm via surface deposition of NIPS. Besides the better hydrophilicity, what’s interesting is that the BSA rejection ratio increases from 48% to 94% with the increase of SMA, which indicates that the separation performance has improved. This strategy can be conveniently extended to the creation of firmly thin layer, surface functionalization and structure controllability of the membrane. [ABSTRACT FROM AUTHOR]

Polysulfone (PSF) membranes have gained great attention in the fields of ultrafiltration, microfiltration, and thin film composite membranes for nanofiltration or reverse osmosis. For the first time, it is proposed to fabricate PSF membranes via thermally induced phase separation (TIPS) process using diphenyl sulfone (DPSO2) and polyethylene glycol (PEG) as mixed diluent. DPSO2 is chosen as a crystallizable diluent, while PEG is considered in terms of molecular weight ( M ) and dosage. We systematically investigate the interactions between PSF, DPSO2 and PEG based on the simulation calculations and solubility parameter theory. It is inferred that DPSO2 has an excellent compatibility with PSF, and the addition of PEG results in the ternary system thermodynamically less stable and then facilitates its liquid-liquid (L-L) phase separation. SEM images indicate that cellular-like pores are obvious throughout the membrane when the PEG content in the mixed diluent is 25 wt%−35 wt%. We can facilely manipulate the pore size, water flux and mechanical properties of PSF membranes with the dosage of PEG-200, the M of PEG or the cooling rate. The successful application of TIPS can provide a new approach for structure manipulation and performance enhancement of PSF membranes. [ABSTRACT FROM AUTHOR]

Polysulfone (PSF) membranes were successfully prepared by thermally induced phase separation (TIPS) using dipropylene glycol dibenzoate (DPGDB) as the diluent for the first time. Interestingly, the typically liquid-liquid (L-L) phase separation with coarsening process was not observed and the gelation occurred for the system during the cooling process. Moreover, the cross-section morphologies of all the membranes showed the network structure for the PSF concentration is in the range of 17wt%–21wt%. The membrane formation mechanism concerning the phase separation-gelation was proposed. The rejection of bovine serum albumin (BSA) of the membrane increased from 83.5% to 95.9% with the increase of PSF concentration. Additionally, the maximum break strength the membrane was as high as 7.3 MPa. The present study may open a new method to fabricate PSF membrane and control membrane structure. [ABSTRACT FROM AUTHOR]

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Copyright of Chinese Journal of Chemical Physics (1674-0068) is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Construction of the hierarchical surface topographies is advantageous to develop the highly-permeable membrane with super hydrophobicity, which is conductive to the precise purification of water-in-oil emulsions. Herein, the robust superhydrophobic poly(vinylidede) fluoride (PVDF) membrane with the artificially tunable surface topographies was constructed by spraying the hydrophobic silicon dioxide (SiO 2) particles onto the nascent cast film prior to the thermally induced phase separation. Benefiting from the self-adhesive property of PVDF, the SiO 2 particles of two different sizes were firmly immobilized to the membrane surface, endowing resultant membranes with the micro-nano coarse structure and therefore the specific characteristic of super-hydrophobicity. The resulted membrane prepared at the optimal conditions exhibited the water contact angle and the water sliding angle of 160 ± 4° and 3 ± 2° respectively, accompanied with the averaged pore size of 330.8 ± 11.0 nm. Accordingly, it displayed the improved permeation fluxes of 1698 ± 119 L∙m−2∙h−1 and 2000 ± 129 L∙m−2∙h−1 with regard to the separation of the water-in-toluene and water-in-chloroform emulsions respectively, along with the separating efficiencies of 99.0 ± 0.2% and 98.7 ± 0.2% in terms of the oil purity in the penetrated solutions. Besides, the favorable reusability and stability of fabricated membranes demonstrated by the destructive experiments and cyclic performance tests might provide guarantee for the industrial water-in-oil emulsions purification. [Display omitted] • Spraying-assisted construction of superhydrophobic PVDF membrane was proposed. • Immobilized SiO 2 particles with hierarchical topographies favor the super hydrophobicity. • The membrane showed a flux of ∼2000 L∙m−2∙h−1 and oil purity of ∼99.0%. • The fabricated membranes show good reusability and stability. [ABSTRACT FROM AUTHOR]

Oxygenation membranes in extracorporeal membrane oxygenation (ECMO) with excellent gas permeability, good hemocompatibility and durable resistance to plasma leakage is the key to achieve long-term and efficient blood oxygenation. This study put forward surface segregation strategy in thermally induced phase separation (TIPS) of poly (4-methyl-1-pentene) (PMP) membranes to realize the in-situ surface modification. Heterostructured PMP membranes with hydrophilic hemocompatible surface and hydrophobic body were obtained by migration of hydrophilic segments of the amphiphilic block copolymer Pluronic F127 to the surface in their preparation process. The hydrophilic surface could effectively improve hemocompatibility of membranes through hydration layer effect and steric hindrance effect, also reduce platelet adhesion significantly, and prolong the coagulation time of the four coagulation items within the normal physiological range of human body. When adding 10 wt% F127, the membrane exhibited an optimum CO 2 permeance of ∼11461 GPU and O 2 permeance of ∼13335 GPU, respectively, and an optimized blood oxygenation performance in vitro with O 2 flux of 122.9 ml min−1 m−2 and CO 2 flux of 129.2 ml min−1 m−2, and the asymmetric structure ensures resistance to plasma leakage for more than two months, that showed great application potential. Besides, preparation of hollow fiber membranes based on surface segregation was also explored, aiming to realize the enhanced performance and large-scale preparation of PMP oxygenation membranes. The membranes prepared in this work exhibited an outstanding performance when applied in blood oxygenation, showing great application potentials. [Display omitted] • PMP-F127 membranes were fabricated via surface segregation. • The membrane has a hemocompatible skin layer and an asymmetric support layer. • The membrane shows good gas permeability and long-term stability. • A large-scale PMP/F127-10 hollow fiber oxygenation membranes were prepared. [ABSTRACT FROM AUTHOR]

In recent years, polyketone (PK) porous membranes have attracted significant attention in separation technology owing to its high tolerance to organic solvents. However, its excellent solvent resistance complicates PK membrane preparation procedure, requiring the use of toxic solvents in the conventional nonsolvent induced phase separation (NIPS) method. In this study, the thermally induced phase separation (TIPS) method was explored to prepare porous membranes with PK homopolymer and copolymer. By screening many diluents, we found potential diluents that could be applied to the TIPS method for PK membrane preparation. Two kinds diluent (PEG300 and DPrP) for CPK and one kind pure diluent (PEG200) for HPK were screened to induce L-L phase separation. In the membrane preparation by the liquid – liquid (L - L) phase separation system, the influence of the PK type, cooling conditions, and polymer concentration on the final membrane structure was investigated. Finally, the porous structure, water permeance, and mechanical properties of the membranes prepared using the NIPS and TIPS methods were compared. Prepared CPK and HPK membrane with 25 wt% concentration by TIPS method showed high water permeability (400 and 480 L m−2h−1bar−1) and tensile strength (4.6 and 4.9 MPa). This study will facilitate the development of high-performance PK membranes using the TIPS method, particularly in the selection of diluents. [Display omitted] • Porous polyketone (PK) membranes were successfully developed via TIPS method. • Diluents induced liquid-liquid phase separation for two kinds of PK was screened. • The effect of cooling rate and PK concentration on membrane was investigated. • PK membrane prepared by TIPS method showed high permeability and tensile strength. [ABSTRACT FROM AUTHOR]

We describe two studies encompassing the iterative refinement of a polymer-based rhBMP-2 delivery system for bone tissue engineering. Firstly, we compared the bone-forming capacity of porous poly(D,L-lactic-co-glycolic acid) (PLGA) scaffolds produced by thermally induced phase separation (TIPS) with non-porous solvent cast poly(D,L-lactic acid) (PDLLA) used previously. Secondly, we examined the potential synergy between rhBMP-2 and local bisphosphonate in the PLGA scaffold system.In vivo ectopic bone formation studies were performed in C57BL6/J mice. Polymer scaffolds containing 0, 5, 10 or 20 µg rhBMP-2 were inserted into the dorsal musculature. At all rhBMP-2 doses, porous PLGA produced significantly higher bone volume (BV, mm3) than the solid PDLLA scaffolds. Next, porous PLGA scaffolds containing 10 µg rhBMP-2 ± 0.2, or 2 µg zoledronic acid (ZA) were inserted into the hind-limb musculature. Co-delivery of local 10 µg rhBMP-2/2 µg ZA significantly augmented bone formation compared with rhBMP-2 alone (400 % BV increase, p < 0.01). Hydroxyapatite microparticle (HAp) addition (2 % w/w) to the 10 µg rhBMP-2/0.2 µg ZA group increased BV (200 %, p < 0.01). We propose that this was due to controlled ZA release of HAp-bound ZA. Consistent with this, elution analyses showed that HAp addition did not alter the rhBMP-2 elution, but delayed ZA release. Moreover, 2 % w/w HAp addition reduced the scaffold’s compressive properties, but did not alter ease of surgical handling.In summary, our data show that refinement of the polymer selection and scaffold fabrication can enhance rhBMP-2 induced bone formation in our bone tissue engineering implant, and this can be further optimised by the local co-delivery of ZA/HAp.

In this study we used a biocomplex constructed from dental pulp stem/progenitor cells (DPCs) and a collagen sponge scaffold for oro-maxillo-facial (OMF) bone tissue repair in patients requiring extraction of their third molars. The experiments were carried out according to our Internal Ethical Committee Guidelines and written informed consent was obtained from the patients. The patients presented with bilateral bone reabsorption of the alveolar ridge distal to the second molar secondary to impaction of the third molar on the cortical alveolar lamina, producing a defect without walls, of at least 1.5 cm in height. This clinical condition does not permit spontaneous bone repair after extraction of the third molar, and eventually leads to loss also of the adjacent second molar. Maxillary third molars were extracted first for DPC isolation and expansion. The cells were then seeded onto a collagen sponge scaffold and the obtained biocomplex was used to fill in the injury site left by extraction of the mandibular third molars. Three months after autologous DPC grafting, alveolar bone of patients had optimal vertical repair and complete restoration of periodontal tissue back to the second molars, as assessed by clinical probing and X-rays. Histological observations clearly demonstrated the complete regeneration of bone at the injury site. Optimal bone regeneration was evident one year after grafting. This clinical study demonstrates that a DPC/collagen sponge biocomplex can completely restore human mandible bone defects and indicates that this cell population could be used for the repair and/or regeneration of tissues and organs.

Nano-fibrous scaffolds which could potentially mimic the architecture of extracellular matrix (ECM) have been considered a good candidate matrix for cell delivery in tissue engineering applications. In the present study, a semicrystalline diblock copolymer, poly(e-caprolactone)-block-poly(L-lactide) (PCL-b-PLLA), was synthesized and utilized to fabricate nano-fibrous scaffolds via a thermally induced phase separation process. Uniform nano-fibrous networks were created by quenching a PCL-b-PLLA/THF homogenous solution to -20ºC or below, followed by further gelation for 2 hours due to the presence of PLLA and PCL microcrystals. However, knot-like structures as well as continuously smooth pellicles appeared among the nano-fibrous network with increasing gelation temperature. DSC analysis indicated that the crystallization of PCL segments was interrupted by rigid PLLA segments, resulting in an amorphous phase at high gelation temperatures. Combining TIPS (thermally induced phase separation) with salt-leaching methods, nano-fibrous architecture and interconnected pore structures (144±36 mm in diameter) with a high porosity were created for in vitro culture of chondrocytes. Specific surface area and protein adsorption on the surface of the nano-fibrous scaffold were three times higher than on the surface of the solid-walled scaffold. Chondrocytes cultured on the nano-fibrous scaffold exhibited a spherical condrocyte-like phenotype and secreted more cartilage-like extracellular matrix (ECM) than those cultured on the solid-walled scaffold. Moreover, the protein and DNA contents of cells cultured on the nano-fibrous scaffold were 1.2-1.4 times higher than those on the solid-walled scaffold. Higher expression levels of collagen II and aggrecan mRNA were induced on the nano-fibrous scaffold compared to on the solid-walled scaffold. These findings demonstrated that scaffolds with a nano-fibrous architecture could serve as superior scaffolds for cartilage tissue engineering.

In this study, we successfully prepared fly ash-based SiO 2 -Al 2 O 3 microspheres using phase separation followed by acid leaching. Thermal analysis and X-ray diffraction were used to identify the optimal temperature range of heat treatment. The chemical composition and surface property of the microspheres were analyzed using X-ray fluorescence and contact angle measurements, and scanning electron microscopy was used to characterize the appearance of the microspheres. The results showed that the SiO 2 -Al 2 O 3 microspheres were composed of 60–80 wt% SiO 2 and 10–12 wt% Al 2 O 3 with a uniform particle size, a hydrophilic surface, and high alkali resistance. Heat treatment studies revealed that the phase separation temperature should not exceed 900 °C to avoid crystallization. The mean particle size of the SiO 2 -Al 2 O 3 microspheres decreased with an increase in the heat treatment temperature. Additionally, observing the evolution of the phase structure at 800 °C showed that there was fusion between the SiO 2 -Al 2 O 3 -enriched phases via interfacial tension in the later stage, resulting in larger spherical phase structures. Further, an increase in the Al 2 O 3 , Fe 2 O 3 , and CaO composition decreased the SiO 2 -Al 2 O 3 microspheres particle size, and therefore inhibited phase separation. [Display omitted] [ABSTRACT FROM AUTHOR]

Superhydrophobic-superoleophilic poly(ethylene chlorotrifluoroethylene) (ECTFE)-SiO 2 hybrid porous membrane with hierarchical micro/nano-structural surface was successfully fabricated via thermally induced phase separation (TIPS) method using bis(2-ethylhexyl) adipate (DEHA) and diethyl phthalate (DEP) as binary diluent, hydrophobic SiO 2 as the additive. The effect of SiO 2 content on the morphology, pore size distribution, wettability and mechanical properties of prepared membrane was characterized by scanning electron microscope, automatic mercury porosimeter, contact angle goniometer and tensile testing instrument, respectively. The results showed that, the prepared hybrid membrane surface evolved into superoleophilic and superhydrophobic when the SiO 2 content was 4 wt%. The separation experiments for different kinds of surfactant-free and surfactant-stabilized water-in-oil emulsions indicated that prepared superhydrophobic-superoleophilic membrane had high oil/water separation efficiency. The antifouling performance of the membrane was also studied for reuse many times in various pH conditions. This study provided a novel material and a facile method to fabricate superhydrophobic-superoleophilic membrane. [ABSTRACT FROM AUTHOR]

Recently, monoliths with continuous porous structure have received much attention for high-performance separation/adsorption matrix in biomedical and environmental fields. This study proposes a novel route to prepare cellulose monoliths with hierarchically porous structure by selecting cellulose acetate (CA) as the starting material. Thermally induced phase separation of CA solution using a mixed solvent affords a CA monolith, which is converted into the cellulose monolith by alkaline hydrolysis. Scanning electron microscopy images of the CA and cellulose monoliths reveal a continuous macropore with rough surface, and nitrogen adsorption/desorption analysis indicates the formation of a mesoporous structure. The macroporous structure could be controlled by changing the fabrication parameters. A series of reactive groups are introduced by chemical modifications on the surface of the cellulose monolith. The facile and diverse modifiability combined with its hydrophilic property make the hierarchically porous cellulose monolith a potential platform for use in separation, purification and bio-related applications. [ABSTRACT FROM AUTHOR]

This study deals with fabrication of amine-functionalized acrylic monoliths and their application for separation media. Poly(glycidyl methacrylate- co-methyl methacrylate) (PGMA) monoliths with three-dimensional interconnected porous structure were prepared by thermally induced phase separation (TIPS) using cosolvent system, and subsequent aminolysis of oxirane groups produced amine-functionalized acrylic monoliths. The porous structure and specific surface area of the monoliths were dependent on the molecular weight of PGMA. Bovine serum albumin (BSA) was effectively adsorbed on the monoliths by electrostatic interaction, and the binding capacity was enhanced with an increase in the surface area of the monoliths. Furthermore, the amine-functionalized monoliths released BSA by washing with high salt concentration solution. These results demonstrated a potential of the amine-functionalized monoliths prepared by TIPS method for rapid separation and analysis of biomolecules. [ABSTRACT FROM AUTHOR]

Scaffolds with porous structures are highly applicable for tissue engineering and regenerative medicine. In the present study, 3-dimensional poly(propylene fumarate-co-caprolactone) [P(PF-co-CL)] scaffolds were fabricated from a P(PF-co-CL)-dioxane-water ternary system through thermally induced phase separation (TIPS). Cloud points of P(PF-co-CL) in dioxane-water solutions increased with increased solute concentration, but increased dioxane composition decreased cloud point. Among 3 polymer concentrations (4, 8, and 12 wt%), 8 wt% P(PF-co-CL) scaffolds exhibited the best pore interconnectivity, with large, regular sized pores. Scaffolds were formed in 3 solutions with different dioxane-water ratios (74/26, 78/22, and 82/18 wt/wt); the 78/22 wt/wt scaffold had finger-shaped patterns with better interconnectivity than scaffolds from the other two ratios. Higher dioxane-water ratios resulted in a larger contact angle and thus less wettability for the fabricated scaffold, while scaffolds fabricated from higher concentrations of P(PF-co-CL) or high dioxane-water ratios had better biomineralization after soaking in simulated body fluid. In vitro cell viability testing showed the scaffolds had good biocompatibility with both bone and nerve cells. The results indicate that the polymer concentration and solvents ratio significantly affect the formation of porous structures, and optimum processing parameters were found to be 8% polymer concentration and 22% to 24% water content. These porous P(PF-co-CL) scaffolds fabricated via TIPS may be useful in various tissue engineering applications © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 226-235, 2017. [ABSTRACT FROM AUTHOR]

Rigid poly(lactic acid) (PLA) foams were prepared by thermally induced phase separation followed by solvent exchange and vacuum drying. A novel tetrahydrofuran (THF)/water solvent system was used for the induction of liquid-liquid phase separation of PLA solution at three different temperatures; 24 °C, 4 °C and −20 °C. PLA gels obtained were mechanically stabilized by replacing THF/water solvent mixture with ethanol nonsolvent. Characterization of rigid PLA foams was obtained by scanning electron microscopy, mercury intrusion porosimetry, x-ray diffractometry, infrared spectroscopy and differential scanning calorimetry analyses. Effects of fabrication parameters on the morphology and pore structure were systematically examined. The parameters investigated included; (i) polymer concentration, (ii) THF/water ratio and (iii) quench temperature. Results showed that degree of porosity and the morphology of the pores, such as the pore size and shape could be controlled by tuning the fabrication parameters. By controlling the degree of phase separation of PLA solution, foams with dual micro and nano structures were obtained. [ABSTRACT FROM AUTHOR]

We report the preparation and performance of poly(acrylonitrile-methacrylate) (AN-MA) flat-sheet membranes with various MA feeding ratio via thermally induced phase separation, in which the membrane forming system consisted of AN-MA, ethylene carbonate (EC), and triethyl citrate (TEC). The effects of the preparation conditions, such as the MA feeding mole ratio, EC content in the mixed diluent, and AN-MA concentration on the pore structure, porosity, water flux, and mechanical properties of the AN-MA membranes were studied. The poly(acrylonitrile-methacrylate) (AN-MA mole ratio 85/15, 80/20, 75/25) copolymers were synthesized by emulsion polymerization. The AN-MA copolymers are melt processable in the temperature range of 130–180°C. The morphology of the resulting membrane gradually changes from a typical bicontinuous structure to a cellular structure upon increasing the polymer concentration and EC content in the mixed diluent. The water flux of AN-MA microporous membranes increased and subsequently declined as the MA feeding molar ratio increased in the polymerization system. In addition, the mechanical properties of the AN-MA membranes increased gradually. Consequently, the properties of the AN-MA membranes were optimal when the MA feeding molar ratio was 20 mol%. Correspondingly, the membrane exhibits a relatively high water flux (66.0 L/(m2 h)) and porosity (75%) when the ternary system contains 60 wt.% EC in the mixed diluent and 9 wt.% 80/20AN-MA. In addition, the membrane exhibits a higher tensile strength (4.6 MPa) and elongation (43.8%). [ABSTRACT FROM PUBLISHER]

Dual-asymmetric poly(vinylidene fluoride) (PVDF) separators have been fabricated by thermally induced phase separation with dimethyl sulfone (DMSO2) and glycerol as mixed diluents. The separators have a porous bulk with large interconnected pores (~1.0 μm) and two surfaces with small pores (~30 nm). This dual-asymmetric porous structure endows the separators with higher electrolyte uptake amount and rapider uptake rate, as well as better electrolyte retention ability than the commercialized Celgard 2400. The separators even maintain their dimensional stability up to 160 °C, at which temperature the surface pores close up, leading to a dramatic decrease of air permeability. The electrolyte filled separators also show high ion conductivity (1.72 mS∙cm) at room temperature. Lithium iron phosphate (LiFePO)/lithium (Li) cells using these separators display superior discharge capacity and better rate performance as compared with those from the commercialized ones. The results provide new insight into the design and development of separators for high-performance lithium ion batteries with enhanced safety. [ABSTRACT FROM AUTHOR]

Nanofibrous tubular poly( L -lactic acid) (PLLA) scaffolds were fabricated by centrifugation combined with thermally induced phase separation technique using PLLA/1,4-dioxane/water ternary system, at input voltage of 4.00 V and phase separation temperature of −15 °C. Addition of sucrose led to the generation of porous scaffolds with interconnected pores. Input voltage was the crucial factor to generate nanofibrous tubular scaffold that mimicked the structural features of the biological systems. The surface of nanofibrous tubular scaffold provided a good environment for attachment and proliferation of MC3T3-E1 subclone 14 cells, exhibiting significant potential for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

Three different thickness isotactic polypropylene (iPP) hollow fiber membranes were prepared for air gap membrane distillation (AGMD) via thermally induced phase separation (TIPS) with cosolvent di-n-butyl phthalate and dioctyl phthalate. A study was carried out to investigate the effect of membrane thickness on the water flux and mechanical properties of the membranes. The ratio of membrane thickness to membrane inner diameter was constant at 0.2. Three relevant AGMD modules were fabricated. During AGMD of 6 wt% salt solution, the influence of inlet temperature of cold brine feed (T1), membrane thickness on permeate water flux (JD), gained output ratio (GOR), and thermal efficiency (TE) was experimentally investigated. The maximumJDcould reach 6.62 kg/m2 h and the maximum GOR could reach 6.95, respectively. Furthermore, the maximum TE was 89.42% which was much higher than that of traditional membrane distillation modules. The results demonstrated that the prepared iPP hollow fiber membrane by TIPS method would be of great potential to be utilized in AGMD process for desalination. [ABSTRACT FROM PUBLISHER]

To date, remarkable progress has been achieved in the fabrication of poly(vinylidene fluoride) (PVDF) membranes with high performance for applications in wastewater treatment. After a comprehensive overview of recent progress on the preparation of PVDF membranes via thermally induced phase separation (TIPS) method, this paper provided historical information about the plenty of work focused on the preparation and advanced industrialization of PVDF membranes that was carried out by Beijing Key Laboratory of Membrane Materials and Engineering of Tsinghua University (Beijing, China). The work followed the line of formula design, advanced production, and membrane module development. Firstly, an innovative PVDF membrane with good performance was prepared via TIPS (liquid–liquid, L–L) method based on exhaustive thermodynamic and dynamic researches on the membrane formation process. Secondly, advanced production of the PVDF hollow fiber membrane was achieved by an effective combination of material processing and unit operation. Additionally, different ultrafiltration (UF) modules were fabricated according to various application situations. The final step explored the possibility of using an integrated membrane solution that adopted the modules where wastewater treatment was intended for water recycling, as shown in four application cases. The application results have shown that PVDF membranes prepared via TIPS (L–L) method break through the traditional phase separation limitation and exceed performance expectation. This paper can be a useful reference for the preparation and development of polymeric membranes and modules. [ABSTRACT FROM AUTHOR]

A novel methodology based on dissipative particle dynamics (DPD) simulation and the results of macroscopic mathematical models was established to obtain multiscale understanding on the membrane formation process via thermally induced phase separation (TIPS) method accompanied with heat transfer between the polymer solution and coagulation bath, taken into account polyvinylidene fluoride - diphenyl carbonate (PVDF-DPC) system. The phase separation process simulated by this methodology could be close to a real membrane formation process by adopting a linear cooling algorithm based on the macroscopic model results and providing much larger scales. The simulation results indicated that the temperature gradient in the polymer solution resulted from the heat transfer at the polymer solution-coagulation bath interface had a significant influence on the phase separation process, thereby different parts in the polymer solution possessed different cooling rates and coarsen time, which resulted in a microporous membrane with anisotropic structure. Secondly, as the polymer concentration increased, the system became much denser and the phase separation rate got lower due to a decline in the flexibility of the system. The results proved that a further deep understanding could be obtained by this methodology. [ABSTRACT FROM AUTHOR]

Dissipative particle dynamics (DPD) simulation was performed to construct the mesophase membrane morphologies of poly(4-methyl-1-pentene) (PMP) during thermally induced phase separation (TIPS). The PMP morphologies and their fluid diffusivities relationship was established using a mesoscale 3-D tetragonal-like structure construction. The effects of PMP concentration and the use of a single diluent (dioctyl phthalate, diphenyl ether, and dibutyl phthalate) or a mixed diluent on the pore morphology were compared. The diffusivity resistance was evaluated by comparing the mean square displacement of a hypothetical fluid bead through tetragonal-like morphologies in three normal directions. The 3-D morphology and density profile results revealed that larger pores were produced after TIPS when the PMP-diluent interaction was weaker. Radial distribution function analysis showed that poor diluent and high PMP concentration could form a coarsened structure with less interconnectivity, indicating more diffusion resistance. To verify DPD simulation results, PMP hollow fibre membranes (HFMs) were fabricated via TIPS, and HFM cross-sectional morphologies proved that the pore structures agreed with the DPD-simulation 3-D evolution diagram. The structure-fluid diffusivity resistance relationship was also confirmed by porosity measurements and gas permeation testing. The DPD simulation method is promising for the fabrication and design of gas-diffusive membranes, especially in terms of the rational selection of diluent and polymer concentration. [ABSTRACT FROM AUTHOR]

The ECTFE membrane with bicontinuous structure was prepared by a binary diluent via thermally induced phase separation method. The effect of binary diluent composition on membrane structure was investigated systematically. The Flory–Huggins interaction parameters between ECTFE and diluents were investigated to analyze the mechanism of phase separation. Dibutyl sebacate (DBS) was selected as the primary diluent due to the high boiling point and strong interaction with ECTFE, while triphenyl phosphite (TPP) was selected as the secondary diluent because of the good compatibility with DBS. As the weight ratio of DBS to TPP was 3/2, a uniform bicontinuous structure was obtained. A typical upper critical solution temperature behavior was displayed and the monotectic concentration was as high as approximately 50 wt.%. Finally, an ECTFE hollow fiber membrane with a bicontinuous structure was prepared by the binary diluent and revealed high mechanical strength (tensile strength of 2.40 MPa) and filtration performance (water flux of 313 L m−2 h−1at 0.1 MPa). [ABSTRACT FROM PUBLISHER]

A porous poly (ethylene-chlorotrifluoroethylene) (ECTFE) membrane was prepared and evaluated in this study. Initially, solvent screening revealed diethyl phthalate (DEP) and glycerol triacetate (GTA) as proper solvents for the preparation of homogenous ECTFE solutions with the required properties for fabricating a hollow fiber membrane. The thermodynamic phase diagrams for both systems (ECTFE/DEP and ECTFE/GTA) showed a liquid–liquid (L-L) phase separation region, which is needed for a bicontinuous structure, prior to solid–liquid (S-L) phase separation (polymer crystallization). The ECTFE hollow fiber membranes were prepared by a thermally induced phase separation (TIPS) method using a unary solvent (DEP or GTA). The morphologies of hollow fiber membranes were observed by scanning electron microscopy (SEM) and it was observed that a bicontinuous structure was formed through L-L phase separation. The effect of the solvent types on properties of the prepared membrane such as water permeability and mechanical strength was discussed in detail. Moreover, the spherulite growth rate and crystallization degree were measured to assess the differences in the mechanical properties of the membranes prepared using DEP and GTA. In this study, with a polymer concentration of 20 wt%, the membrane showed a superior water flux and comparable mechanical properties with the ECTFE membranes already reported in published papers. Furthermore, the chemical resistance properties of ECTFE hollow fiber membranes were evaluated using the harsh treatments. [ABSTRACT FROM AUTHOR]

Polymeric gel membranes contain poly(ether- b -amide) (Pebax) and ethylene glycol monophenyl ether (EPH) was prepared via thermally induced phase separation (TIPS) method for the first time. In the membranes, EPH was used as not only diluent to form the gel structure, but also functional liquid to enhance the CO 2 permeability and CO 2 /N 2 selectivity. Comprehensive investigation was carried out to study the phase separation behaviors and membrane performances. Phase diagrams and optical microscope results indicate that the crystallizition of Pebax from a one-phase solution is responsible for the physical network structure of the gel membranes. Meantime, the gel temperature shifted to the lower region with increasing EPH content. Both the pure CO 2 permeability and CO 2 /N 2 ideal selectivity of the membranes were simultaneously increased with the increase of EPH content, which can be ascribed to the multiple synergistic effect of (a) the increased solubility of CO 2 by Lewis acid-base interactions between CO 2 and ethylene oxide groups in EPH, (b) the barrier effect of EPH on the transport of N 2 and (c) more permeable amorphous phase was formed in polymer matrix. The overall performance of gel membranes with 60 and 80 wt% EPH fall within the attractive region beyond the “Robeson Upper Bound” for CO 2 /N 2 gas pairs. The successful application of TIPS provides a new route to the structure modulation and performance enhancement of polymer gel membranes in the removal of CO 2 from gas streams. [ABSTRACT FROM AUTHOR]

A Maxwell–Stefan model was firstly established to describe the mass and heat transfer in the air gap and coagulation bath stages via thermally induced phase separation (TIPS) process. A cylindrical configuration was considered with the polyvinylidene fluoride-diphenyl carbonate system. The model results showed that firstly, in the air gap, a polymer concentration gradient was induced in the polymer solution due to the diluent evaporation, and with an increase in the evaporation time, the gradient increased gradually. When the initial polymer concentration decreased, the polymer concentration gradient increased while the concentration gradient depth decreased due to a reduction in the diffusion coefficient. Secondly, the temperature of the polymer solution declined rapidly when it was immersed in the coagulation bath, which resulted in a temperature gradient in the solution. The temperature gradient diminished as the quenching time increased because of the heat transfer at the polymer solution–coagulation bath interface. In addition, with the initial polymer concentration decreasing, the solution heat transfer coefficient raised a little, which caused a slight rise in the temperature gradient. Finally, the model results were validated by the experiments to obtain a beneficial reference for the formation of polymeric microporous materials via TIPS. [ABSTRACT FROM AUTHOR]

Monolith-like particles (MLP) are a new base bead architecture optimized for industrial chromatographic downstream processing of very large targets such as whole viral particles (5–300 nm diameter). They have been designed with large pore size though-channels to facilitate access of large diameter targets to the intraparticle chromatographic surface. Herein we describe a novel MLP bead architecture that have been fabricated and characterized for virus purification. This is the first study to demonstrate cellulose-based MLP beads applied for bioseparation of viral particles. The MLP was produced from cellulose acetate by a combined concept of thermally induced phase separation and oil-in-water emulsification. Hydrolyzation, cross-linking, and surface modification with dextran sulfate were carried out for pseudo-affinity chromatographic applications. Scanning electric microscopy analysis showed the presence of large pores that penetrated from the outer surface to within the intraparticle structure. Mercury intrusion porosimetry analysis estimated the mode pore radius to be 1.5 µm. For influenza A virus purification, the MLP surface modified with dextran sulfate exhibited significant higher dynamic binding capacity compared with commercial resins, Cellufine Sulfate and Capto DeVirS. These results demonstrate that viral particles can access the intraparticle surface within these novel large through-pore MLP beads. The novel MLP base architecture described in this study will be a useful support matrix for giant biomolecule and whole viral particle purification. • Monolith-like particles (MLP) were fabricated into chromatographic resin. • The through-pores in the MLP were estimated to have a mode pore radius of 1.5 µm. • Dextran sulfate was used to modify the MLP to promote pseudo-affinity capture of Influenza virus. • For Influenza virus, DBC 10% of the MLP was 5–11 times higher than that of commercial resins. [ABSTRACT FROM AUTHOR]

This original report addresses an innovative concept for generating doubly porous poly(2-hydroxyethyl methacrylate) (PHEMA)-based materials via thermally induced phase separation (TIPS). A co-solvent mixture constituted of water and 1,4-dioxane was used to solubilize linear PHEMA chains, followed by a solidification process by quenching the PHEMA/co-solvent mixture at a given temperature, and subsequent freeze-drying to produce the corresponding biporous PHEMA materials. Critical physico-chemical parameters, such as the quenching temperature, the co-solvent volume ratio, and the polymer concentration, were carefully investigated to clearly understand their effects on pore size and morphology. Anisotropic macropores with a tubular shape in the 10–100 μm size range were generally obtained, along with various nanoporous structures within the macropore walls. One such lower porosity level displayed pore sizes ranging from about 40 nm to 800 nm, depending on the parameters used to fabricate the doubly porous frameworks. The possibility of cross-linking the porous materials engineered by TIPS was finally examined by taking advantage of the reaction between hydroxyl groups of PHEMA with different acyl dichlorides, which could pave the way for further potential applications in the biomedical area. [ABSTRACT FROM AUTHOR]

This study deals with the fabrication of biodegradable porous materials from bacterial polyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P3HB3HHx), via thermally induced phase separation. P3HB3HHx monoliths with topological porous structure were prepared by dissolution of P3HB3HHx in dimethyl sulfoxide (DMSO) at 85 °C and subsequent quenching. The microstructure of the resulting P3HB3HHx monoliths was changed by the P3HB3HHx concentration of the polymer solution. Differential scanning calorimetry and polarized optical microscope analysis revealed that the P3HB3HHx monoliths crystallized during phase separation and the subsequent aging. The mechanical properties, such as compression modulus and stress, of the monoliths depended on the 3-hydroxyhexanoate content of P3HB3HHx. Furthermore, the P3HB3HHx monolith absorbed linseed oil in preference to water in a plant oil-water mixture. In combination with the biodegradable character of P3HB3HHx, the present study is expected to contribute to the development of bio-based materials. [ABSTRACT FROM AUTHOR]

A review of recent research related to microporous polymeric membranes formed via thermally induced phase separation (TIPS) and the morphologies of these membranes is presented. A summary of polymers and suitable diluents that can be used to prepare these microporous membranes via TIPS are summarized. The effects of different kinds of polymer materials, diluent types, cooling conditions, extractants and additive agents on the morphology and performance of TIPS membranes are also discussed. Finally new developments in TIPS technology are summarized. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Micro- and nano-structured polymer materials have wide application possibilities due to morphology-dependent thermal, acoustic, mechanical and physico-chemical properties. Rapid cooling of polymer dissolved in a suitable solvent can form a micro-structured material and this process is known as the thermally induced phase separation (TIPS). The result of TIPS is a porous material that has foamy or particulate morphologies with varying morphology characteristics, which strongly depend on the mechanism and dynamics of the material formation. We carried out experiments to obtain polymer materials by the TIPS method in dependence on the initial polymer concentration and quantitatively compared the resulting morphologies to the predictions of the Cahn–Hilliard model, which describes the dynamics of morphology evolution. The model predicts the correct type of morphology and cell size in dependence on the initial polymer concentration. Model results also explain the heterogeneity of the produced material. The quantitative understanding of polymer foam morphology evolution by TIPS opens a way for the prediction and control of morphologies of polymeric foams created by other routes involving phase separation. [ABSTRACT FROM AUTHOR]

Porous carbon membranes were favorably fabricated through the pyrolysis of polyacrylonitrile (PAN) precursors, which were prepared with a template-free technique-thermally induced phase separation. These carbon membranes possess hierarchical pores, including cellular macropores across the whole membranes and much small pores in the matrix as well as on the pore walls. Nitrogen adsorption indicates micropores (1.47 and 1.84 nm) and mesopores (2.21 nm) exist inside the carbon membranes, resulting in their specific surface area as large as 1062 m/g. The carbon membranes were used to adsorb organic dyes (methyl orange, Congo red, and rhodamine B) from aqueous solutions based on their advantages of hierarchical pore structures and large specific surface area. It is particularly noteworthy that the membranes present a selective adsorption towards methyl orange, whose molecular size (1.2 nm) is smaller than those of Congo red (2.3 nm) and rhodamine B (1.8 nm). This attractive result can be attributed to the steric structure matching between the molecular size and the pore size, rather than electrostatic attraction. Furthermore, the used carbon membranes can be easily regenerated by hydrochloric acid, and their recovery adsorption ratio maintains above 90% even in the third cycle. This work may provide a new route for carbon-based adsorbents with hierarchical pores via a template-free approach, which could be promisingly applied to selectively remove dye contaminants in aqueous effluents. [ABSTRACT FROM AUTHOR]

The nonisothermal crystallization kinetics of poly(vinylidene fluoride) (PVDF) in PVDF/polymethyl methacrylate (PMMA)/dipropylene glycol dibenzoate (DPGDB) blends, where DPGDB served as a diluent, via solid–liquid (S-L) phase separation during a thermally induced phase separation process was investigated through differential scanning calorimetry (DSC) measurements. It was found that the Ozawa model could only describe the nonisothermal crystallization behavior of PVDF/PMMA/DPGDB system to some extent. The influence of the cooling rate and PMMA/PVDF weight ratio in the PVDF/PMMA/DPGDB system on the crystallization mechanism was also examined based on the Avrami–Jeziorny method and Mo method. Primary crystallization and secondary crystallization were observed in the Avrami–Jeziorny analysis. The analysis by the Avrami–Jeziorny and Mo models indicated that the increase of PMMA/PVDF weight ratio decreased the crystallization rate during the primary crystallization stage. The results showed that the Mo method could well explain the kinetics of the primary PVDF crystallization. The Avrami–Jeziorny method, however, could not well describe the nonisothermal crystallization process of PVDF in the primary crystallization stage. The activation energy, determined by the Kissinger method, was not suitable to reflect the PVDF crystallization process in the PVDF/PMMA/DPGDB system. [ABSTRACT FROM PUBLISHER]