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The primary objective of this study was the investigation of thermo-mechanical behavior of cellulosic fiber reinforced polylactid (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biopolymers. Both PLA and PHBV were processed with 30 wt % of cellulosic fibers; moreover, to improve the processability and mechanical performance, PHBV was previously blended with 30% by weight poly(butylene adipate-co-butylene terephthalate) (PBAT). Secondary target was the comparison of the obtained results to natural fiber reinforced polypropylene (PP) composites reinforced with exact the same fibers and processed by using identical techniques. For validation the thermo-mechanical properties, a dynamic mechanical thermal analysis (DMTA) was applied. Storage modulus (E′), loss modulus (E″), and loss factor (tan δ) were determined. The DMTA results indicate decreased polymer chain motion with resulting improvement of stiffness expressed by the storage modulus. Finally, the effectiveness of fiber on the moduli was investigated. The C coefficient differs in dependence on fiber type, use of coupling agent, and the reference temperature in glassy state. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3175–3183, 2013

In this study, we investigated the draping behavior of jute woven fabric to study the feasibility of using natural fabrics in place of synthetic glass-fiber fabrics. Draping behavior describes the in-mold deformation of fabrics, which is vital for the end appearance and performance of polymer composites. The draping coefficient was determined with a common drapemeter for fabrics with densities of 228–765 g/m2 and thread counts under different humidity and static dynamic conditions. The results were compared to glass-fiber fabrics with close areal densities. Characterization of the jute fabrics was carried out to fill the knowledge gap about natural-fiber fabrics and to ease their modeling. The tensile and bending stiffnesses and the shear coupling were also characterized for a plain woven jute fabric with a tensile machine, Shirley bending tester, and picture frame, respectively. As a case study, the draping and resin-transfer molding of the jute fabric over a complex asymmetric form was performed to measure the geometrical conformance. The adoption of natural fibers as a substitute for synthetic fibers, where the strength requirements are satisfied, would thus require no special considerations for tool design or common practices. However, the use of natural fibers would lead to weight and cost reductions. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1453–1465, 2013

Natural fibers are seeing increased use in composite applications due to their reduced cost, low density, and environmen- tal benefits (more sustainable and lower carbon footprint). Although many natural fiber systems have been examined over the last decade, there have been relatively few studies which have compared a variety of fiber types and processing methods directly in the same experimental set. In this study, natural fiber composites made from low density polyethylene (LDPE) and a variety of Canadian based fiber feedstocks were examined including hemp bast, flax bast, chemically pulped wood, wood chips, wheat straw, and mechan- ically pulped triticale. The effect of fiber type, fiber fraction and maleic anhydride polyethylene (MAPE) coupling agent on the me- chanical properties and long-term moisture absorption behavior was quantified. In general, addition of natural fiber to LDPE results in an increase in modulus (stiffness) with a corresponding loss of material elongation and impact toughness. Of the fiber types tested, composites made from chemically pulped wood had the best mechanical properties and the least moisture absorption. However, the use of MAPE coupling agent was found to significantly increase the mechanical performance and reduce moisture absorption for all other natural fiber types. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 969-980, 2013

In this work, we undertook a comparative study of the dynamic dielectric analysis of two composites: natural-fiber-reinforced unsaturated polyester (NFRUP) and E-glass-mat-reinforced unsaturated polyester (EGMRUP). In both composites, two common relaxation processes were identified, the first of which was the α-mode relaxation associated with the glass transition of the matrix. The second one was associated with conductivity that occurred because of the carriers' charge diffusion and was observed at temperatures above the glass transition and at low frequencies. However, the interfacial or Maxwell–Wagner–Sillars polarization was noticed only in the NFRUP composite. This dielectric study also revealed that compared to E-glass fibers, natural fibers enhanced the thermal insulation in the composite. Also, the study of the fiber adhesion in the matrix with scanning electron microscopy, differential scanning calorimetry, and tensile testing revealed a great compatibility of the fibers with the matrix in both composites. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

We report on the dissolution of semi-domestic silk type Antheraea assamensis using ionic liquids. We investigated the impact of different coagulating solvents, including isopropanol and water on the structure and the morphology of the regenerated silk. We found that the water regenerated silk film showed a high β-sheet content and a native silk-like XRD pattern.

Thermal expansivity of chicken feather fibers (CFFs) was studied using thermomechanical analysis for composite applications. CFFs have negative coefficient of thermal expansion (CTE) values in the axial direction at different temperature due to its semicrystalline structure. CFFs have a positive CTE value in the radial direction. The CTE values of epoxy/CFF composites can be predicted by the rule of mixing. CTE values of epoxy/CFF composites in the in-plane direction at various fiber content and temperature have been fully studied and the results can be used in composite design. We can use CFFs in composite materials to control the overall CTE of the composites to reduce the CTE mismatch between the composites and other components. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

With a view of exploring the potential use of natural recourses, we made an attempt to fabricate new Borassus fruit fiber/polypropylene composites by melt mixing method using 5 wt % of fiber. Fibers were chemically modified by alkali treatment using maleated PP (MAPP) as compatibilizer to improve the adhesion between fibers and matrix. Thermal, mechanical, and morphological properties of untreated, alkali treated, and MAPP modified fiber reinforced composites were explored by thermogravimetric analysis, differential scanning calorimetry, universal testing machine, and scanning electron microscopy (SEM), respectively. Thermal stability of the composites was enhanced to some extent on alkali treatment and addition of MAPP. The tensile strength and modulus, flexural strength and modulus, and impact strength were increased for alkali treated/MAPP composites by 4.5%, 17%, 17.2 %, 9%, and 10% respectively. SEM studies on tensile fractured specimens of unmodified composites reveal the poor fiber-matrix interaction, whereas the interaction is strong with enhanced mechanical properties for modified fiber composites. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Recently, the natural fibers-reinforced composites have attracted substantial attention as a potential structural material for low cost applications. The composites of poly(lactic acid) (PLA) with three kinds of natural fibers, such as bamboo fibers, wood fibers, and coconut fibers (CTFs), were prepared by solution-casting technique. The natural fibers were modified by aluminum acid ester coupling agent and stearic acid to improve compatibility. To compare the mechanical and thermal properties of composites, tensile test, dynamic mechanical analysis, differential scan calorimeter, scanning electron microscopy (SEM), and Vicat softening point test were carried. The results showed that the addition of three kinds of natural fibers all could improve the mechanical and thermal properties of composites, and natural fibers after modification could further improve tensile strength of composites. And in comparison, the composite of PLA/CTF had highest tensile strength and best thermal properties. When the content of natural fibers were 2%, the highest tensile strength of PLA/modified CTF composites was highest, and it reached 22.5 Mpa which was 20.4% higher than that of pure PLA, and VST of this composite increased compared with pure PLA. Meanwhile, the results of SEM indicated that the modified CTF had best interfacial compatibility to PLA. These results indicated that PLA/natural fiber composites had higher strength and better heat resistance than pure PLA. This study provided the application of PLA industry with a feasible method. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Numerous strategies to improve the fiber–matrix interaction in natural fiber composites (NFCs) and wood polymer composites (WPCs) have been proposed and investigated. We have reviewed literature on polyolefin-based NFCs and WPCs to get an overview of the current state of the art of compatibilization methods. Those are classified in two categories here, namely fiber-based strategies and matrix-based strategies. Although this issue has been covered by several reviews before, as yet no work exists that is focused on polyolefin-based NFCs and WPCs. Furthermore, a ranking of the compatibilization methods based on their effects on material properties such as tensile/flexural strength and modulus, impact strength and water absorption, allows for an assessment of the efficiency of the various methods. As to the fiber-based strategies, silanes, maleated polyolefins (MA-POs), mercerization and acetylation are most thoroughly investigated. Silanes are most effective judged by achievable material property improvements, allowing for increases in tensile and flexural strength of more than 100%. Among the matrix-based strategies, MA-POs and isocyanates are most prominent in the literature. The first class enables the more significant material improvements, with reported increases of tensile and flexural strength of 132% and 85%, respectively. While strengths can be enhanced by many compatibilization methods, moduli, and impact strength (notched in particular) are in most cases improved to a lesser degree or even reduced. Especially, the last point calls for further attention, because impact strength is still a weak point of NFCs and WPCs. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013

The main objective of this research was to synthesize a new compatibilisant agent (PVC-g-MA), which was grafted from the maleic anhydride on the PVC chains. The presence of maleic anhydride grafting on PVC was made evident by infrared analysis. PVC-g-MA was used like compatibilisant to solve the problem of the incompatibility between the hydrophobic polymeric matrix (PVC) and hydrophilic fiber (alfa). Composites samples were prepared with different alfa fiber loading (10, 20, and 30 wt %) and incorporating PVC-g-MA (1, 3, and 5 wt %) or PP-g-MA (3 wt %). The tensile properties, the thermal stability and the morphology of the composites were investigated. The result indicated that the PVC-g-MA increased the interfacial adhesion between the fibers and the polymer matrix and this effect was better than that obtained for the maleated-polypropylene-coupled composites. Microstructure analysis of the fractured surfaces of MAPP modified composites confirmed improved interfacial bonding. The addition of alfa and PVC-g-MA increased the thermal stability of the composites. The temperature of degradation of the polymer matrix increased about 16°C in comparison to the noncoupled composite, indicating that PVC-g-MA improved the thermal stability of the polymer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Luffa cylindrica of Turkey's Aegean Region was evaluated in terms of fiber characterization and the mechanical properties of its composite with polyester. Characterization of Luffa cylindrica was carried out by Fourier transform infrared spectrophotometer, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and thermogravimetric analysis. Cellulose, hemicellulose, and lignin contents of Luffa cylindirica were also determined. Deconvolutions of XPS data enable determining the distributions of functional groups on the surface of Luffa cylindrica. Luffa cylindrica-reinforced polyester composite was subjected to water aging under a steam of sea-water containing 5% sodium chloride for 170 h at 50 degrees C. After water aging, tensile strength, flexural strength, interlaminar shear strength, and tensile elongation at break values of the composite decreased similar to 28%, 24%, 45%, and 31%, respectively. However, tensile modulus and flexural modulus did not change significantly. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 2330-2337, 2012

In this article, the morphologic transformation of Hibiscus sabdariffa, a natural fiber through graft copolymerization with ethyl acrylate using ceric ammonium nitrate–nitric acid initiator system, has been reported. Different reaction parameters such as temperature, time, initiator concentration, monomer concentration, and pH were optimized to get maximum graft yield (117.3%). The graft copolymer thus formed was characterized by Fourier transform infrared, scanning electron micrographs, X-ray diffraction, thermogravimetric analysis, and differential thermogravimetric analysis techniques. The graft copolymer was found to be moisture, chemical, and thermal resistant. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The influence of chemical modifications, such as dewaxing with hexane and carbon tetrachloride, and alkaline treatment, on the mechanical, thermal, and sorption properties of carnauba straw was investigated for the first time. Scanning electron microscopy showed that the solvent treatments removed the wax layer, exposing the straw fibrils. The straw water sorption capacity was very high, and the treatments turned it from Fickian to non-Fickian. The results show that the solvents used were very effective in removing the surface wax layer, whereas alkali, on the other hand, promoted a more marked change in the chemical structure of the straw. The chemi- cal treatments demonstrated that the wax surface layer was very important in determining the final properties of this material and that its removal reduced the thermal stability and Young's modulus from 143 to 48 MPa and increased its hydrophilicity, changing the contact angle from 90 to 60 � . As a result, carnauba straw is a potentially promising material to be used, for example, as a natural fiber with polymer matrices for the manufacture of low- cost, ecofriendly composite materials. V C 2011 Wiley Periodi- cals, Inc. J Appl Polym Sci 122: 1614-1621, 2011

Self-cleaning polymeric fibers have been successfully prepared by depositing ZnO nanoparticle onto wool and polyacrylonitrile (PAN) fibers with good compatibility and significant photocatalytic self-cleaning activity using the sol-gel process at ambient temperature. scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, diffuse reflectance spectroscopy, X-ray diffraction, Brunauer-Emmett-Teller surface area analysis, and thermogravimetric analysis have been adopted as the characterization techniques. Transmission electron microscopy studies revealed presence of zinc oxide nanoparticles with 10–15 nm in size. Brunauer-Emmett-Teller measurement showed surface area of 48 m2/g for the ZnO nanoparticles. Photocatalytic activity of the self-cleaning materials were tested by measuring the photo-assisted degradation of methylene blue (MB) and eosin yellowish (EY) under ultraviolet-visible illumination. The results indicate that both of the ZnO-coated polyacrylonitrile and ZnO-coated wool fibers acquire photocatalytic activity toward dyes degradation. The photocatalytic activity of the treated fibers is maintained upon several numbers of photodegradation cycles. This facile and cheap preparation technique can be also applied to new polymeric fabrics to produce self-cleaning materials for industrial application. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

In this study, the antifelting and antibacterial features of wool samples treated with nanoparticles of titanium dioxide (TiO2) were evaluated. To examine the antifelting properties of the treated samples, the fabric shrinkage after washing was determined. The antimicrobial activity was assessed through the calculation of bacterial reduction against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. TiO2 was stabilized on the wool fabric surface by means of carboxylic acids, including citric acid (CA) and butane tetracarboxylic acid (BTCA). Both oxidized samples with potassium permanganate and nonoxidized wool fabrics were used in this study. The relations between both the TiO2 and carboxylic acid concentrations in the impregnated bath and the antifelting and antibacterial properties are discussed. With increasing concentration in the impregnated bath, the amount of TiO2 nanoparticles on the surface of the wool increased; subsequently, lower shrinkage and higher antibacterial properties were obtained. The existence of TiO2 nanoparticles on the surface of the treated samples was proven with scanning electron microscopy images and energy-dispersive spectrometry. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The main purpose of this study was producing conductive wool fabric applying carbon nanotubes. Raw and oxidized wool samples were treated with carbon nanotubes in the impregnating bath in the presence of citric acid as a crosslinking agent and sodium hypophosphite as a catalyst while sonicating them in the ultrasonic bath. Electrical resistance, washing durability, and color variation of treated samples were assessed. Through SEM images, the surface morphology of treated samples was studied confirming the surface coating through carbon nanotubes. According to the results, the electrical resistance of treated wool with carbon nanotubes reduced substantially. However, the single-walled carbon nanotubes are more useful to increase the conductivity. In addition, the wool color changed into gray after the treatment.

The relationships between the material parameters, i.e., the fiber fineness, porosity, areal density, layering sequence, and airflow resistivity with the normal- incidence sound absorption coefficient of nonwoven com- posites consisting of three layers have been studied. The monofiber or multifiber needle-punched nonwovens included poly(lactic acid) (PLA), polypropylene (PP), glass fiber, and hemp fibers. Air flow resistivity was statistically modeled and was found to increase with decreasing fiber size and nonwoven porosity. The former models devel- oped for glass fiber mats in the literature were found to be inconsistent with the air flow resistance of the nonwovens reported below. The effects of the layering sequence on air flow resistivity and sound absorption were obtained. It was found that when the layer including reinforcement fibers, i.e., hemp or glass fiber, faced the air flow/sound source, the air flow resistance and the absorption coeffi- cient were higher than the case when the layer including reinforcement fibers was farthest from the air flow/sound source. The difference was more pronounced if there was a greater difference between the resistivity values of the constituent layers of the nonwoven composite. Sound absorption coefficient was statistically modeled in terms of air flow resistivity and frequency. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 3056-3069, 2011

Rice straw fiber-high density polyethylene (HDPE) composites were prepared to investigate the effects of rice straw fiber morphology (rice straw refined fiber, rice straw pellet, rice straw strand), fiber content (20 and 40 wt %), and maleic anhydride polyethylene (MAPE) concentration (5 wt %) on the mechanical and thermal properties of the rice straw fiber-HDPE composites in this study. Rice straw refined fiber exhibited more variability in length and width, and have a higher aspect ratio of 16.3. Compared to the composites filled of rice straw pellet, the composites made of the refined fiber and strand had a slightly higher tensile strength and lower tensile elongation at break. The tensile and flexural strength of the composites increased slightly with increasing rice straw fiber content up to 40 wt %, while the tensile elongation at break decreased. With addition MAPE, the composites filled with 20 wt % rice straw fiber showed an increase in tensile, flexural and impact strength and a decrease in tensile elongation at break. Differential scanning calorimetry showed that the fiber addition and morphology had no appreciable effect on the crystallization temperature of the composites but decreased the crystallinity. The scanning electron microscopy observation on the fracture surface of the composites indicated that introduction of MAPE to the system resulted in promotion in fiber dispersion, and an increase in interfacial bonding strength. Fiber breakage occurred significantly in the composites filled with refined fiber and strand after extruding and injection processing.

Multiple bilayered polysaccharide biofilms have been assembled by electrostatic layer-by-layer (LBL), alternating deposition of cationic chitosan (CS, Mv = 405 kDa) and anionic dextran sulfate (DXS, Mw = 500 kDa) onto ultra-fine cellulose (CELL) and partially hydrolyzed cellulose acetate fibers with diameters ranging from 350 to 410 nm. While the surfaces of partially hydrolyzed (degrees of substitution of 1.14 or 0.2) and CELL fibers were equally hydrophilic, higher surface charges on the more hydrolyzed fibers afford thicker bilayers. The elestrostatic interactions between CS and DXS were enhanced by the presence of NaCl in the dipping and rinsing solutions to allow uniform deposition of sequential polysaccharide bilayers. At 0.25M NaCl, each CS/DXS bilayer averaged 6.4 to 9.0 nm thick with the total thickness of the five bilayer (CS/DXS)5 varied from 64 to 77 nm. The CS/DXS bilayers exhibited much reduced BET surface area and pore volume indicating that these polysaccharides were much more densely packed on the fully hydrolyzed CELL fibers. The findings proofed the concept that long chain polysaccharide electrolytes can be self-assembled as nanometer scale tubular bilayers on ultra-fine cellulose fibers to afford wholly polysaccharidic fibrous architecture. The electrolytic nature, chemical reactivity, and structural versatility of these ultra-high specific surface polysaccharides are advantageous and can be further tuned to serve biological functions and for biomedical applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The objective of this research was to investigate the time-dependent behaviors of yarns, which have significant bearings upon the properties of stretch fabrics made from them. In this study, 100% wool, wool–lycra (W-L) (97 : 3), and polyester–wool–lycra (P-W-L) (52 : 45 : 3) blended yarns were considered. These yarns were subjected to the tensile fatigue failure, stress relaxation, and creep experiments. The findings showed that of these three yarns, P-W-L blend exhibited maximum fatigue lifetime, stress retention, and creep recovery, the pure wool yarn followed suit albeit to a lesser extent, whereas the W-L blend made it least. The investigation suggests that wool alone with lycra as a core component is not sufficient to impart the expected properties upon stretch fabrics, rather a blend of polyester and wool with lycra as in the former would definitely make a worthwhile product. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Various composites of polypropylene (PP) produced using natural fibers such as pineapple leaf fiber, banana fiber, and bamboo fiber were studied for their degree and rate of aerobic biodegradation. Composites used contained 10, 15, and 50% volume fractions of pineapple leaf fiber, banana fiber, and bamboo fiber, respectively, which are the optimum fiber percentages of the respective composites as reported by these authors in their previous works. Cellulose has been used as positive reference material. All the composites exhibited partial biodegradation in the range of 5–15% depending on the fiber content. Degradation had not taken place in the covalent ester linkages between the natural fiber and the MA-g-PP compatibilizer but in those areas of the fibers which have remained only physically embedded in the resin matrix. Thus, although natural fibers reinforced PP composites are not excellent biodegradable material, they can address to the management of waste plastics by reducing the amount of polymer content used that in turn will reduce the generation of nonbiodegradable polymeric wastes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The present article summarizes an experimental study on the effects of two additives on polypropylene/seaweed (PP/SW) biocomposites by dynamic rheological characterization. Storage and loss moduli as a function of frequency were obtained by small-amplitude shear oscillation tests in parallel-plate mode. Maleic anhydride-grafted polypropylene (MAPP) was found to provide good external lubrication, while CNT masterbatch (CESA) promoted fiber–fiber interaction. Han plot and Cole-Cole plot visibly present the difference between the two interaction mechanisms. A synergistic effect was also observed when MAPP and CESA were simultaneously used in biocomposites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The main objective of this study was to determine the effect of intracrystalline and intercrystalline swelling agents and reactive dyes on the accessibility of cotton cellulose to commercial cellulase enzymes. Both types of swelling agents improved the accessibility, and intracrystalline swelling agents showed better results, as the accessibility to difficult-to-reach crystalline regions was increased. As expected, the reactive dyes inhibited the accessibility of the enzymes to some extent. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

A new material of cotton fiber/Al2O3/SiPy+Cl−, COTALPy, was prepared containing on its surface the polymer silsesquioxane 3-n-propylpyridinium chloride strongly adhered. This new composite based on long fibers of natural cotton is chemically stable and had its adsorption properties studied. The COTALPy presented a maximum ionic exchange capacity of 0.85 mmol g−1 by potentiometric titulation. The adsorption isotherms of CuCl2, ZnCl2, CdCl2, NiCl2, and FeCl2 in ethanol solutions were determined for each metal. The adsorption process was studied and data compared with the Langmuir model. The maximum adsorption capacities (in mmol g−1) were: CuCl2 = 0.20, ZnCl2 = 0.18, CdCl2 = 0.35, NiCl2 = 0.22, and FeCl2 = 0.68. Real samples of fuel ethanol were eluted through a column containing the COTALPy, and it presented high-practical potential for removal of metallic ions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The processing variables for making hemp-fiber-reinforced unsaturated polyester (UPE) composites were optimized through orthogonal experiments. It was found that the usage of initiator, methyl ethyl ketone peroxide, had the most significant effect on the tensile strength of the composites. The treatment of hemp fibers with a combination of 1, 6-diisocyanatohexane (DIH) and 2-hydroxylethyl acrylate (HEA) significantly increased tensile strength, flexural modulus of rupture and flexural modulus of elasticity, and water resistance of the resulting hemp-UPE composites. FTIR spectra revealed that DIH and HEA were covalently bonded to hemp fibers. Scanning electronic microscopy graphs of the fractured hemp-UPE composites demonstrated that treatment of hemp fibers with a combination of DIH and HEA greatly improved the interfacial adhesion between hemp fibers and UPE. The mechanism of improving the interfacial adhesion is proposed.

Silk fabric was finished using acrylic acid (AA) as the finishing agent in the presence of sodium citrate and potassium per oxodisulphate catalysts separately or in selected combinations employing a pad-dry-cure technique. Treatment with 6% AA at 30°C and at pH 7 produced optimum effects; a batching time of 45–60 min at 30°C, followed by drying of the batched fabric at 95°C for 5 min and curing of the dried fabric at 140°C for 5 min produced most balanced improvements in the properties such as wrinkle recovery, extensibility, and moisture regain with retention of more than 80% of original strength. Sodium citrate catalyst allowed esterification of AA with proteineous constituent of silk and potassium per sulfate catalyst allowed radical polymerization of free AA or silk bound AA moieties; the said process ultimately led to some degree of crosslinking of the chain polymers of silk. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The biodegradability, morphology, and mechanical properties of composite materials made of poly(butylene succinate adipate) (PBSA) and sugarcane bagasse (SCB) were evaluated. Composites containing maleic anhydride (MA)-grafted PBSA (PBSA-g-MA/SCB) exhibited noticeably superior mechanical properties because of greater compatibility between the two components. The dispersion of SCB in the PBSA-g-MA matrix was highly homogeneous as a result of ester formation between the carboxyl groups of PBSA-g-MA and hydroxyl groups in SCB and the consequent creation of branched and crosslinked macromolecules. Each composite was subjected to biodegradation tests in a Rhizopus oryzae compost. Morphological observations indicated severe disruption of film structure after 60 days of incubation, and both the PBSA and the PBSA-g-MA/SCB composite films were eventually completely degraded. The PBSA-g-MA/SCB films were more biodegradable than those made of PBSA and exhibited a higher intrinsic viscosity, implying a strong connection between these characteristics and biodegradability. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

In this article, N-Methylol dimethylphosphonopropionamide (FR) in combination with a melamine resin (CL), phosphoric acid (PA) catalyst and zinc oxide (ZnO) or nano-ZnO co-catalyst were used (FR-CL-PA-ZnO or nano-ZnO system) to impart flame-retardant property on cotton fabrics. FR-CL or FR-CL-PA-treated cotton specimen showed roughened and wrinkled fabric surface morphology, which was caused by the attack of the FR with slightly acidity. In addition, FTIR analysis showed some new characteristic peaks, carbonyl, CH 2 rocking and CH 3 asymmetric and CH 2 symmetric stretching bands, in the chemical structure of treated cotton specimens. Apart from these, the flame ignited on the flame-retardant-treated fabrics (without subjected to any post-wet treatment) extinguished right after the removal of ignition source. However, FR-CL treated specimens were no longer flame-resistant when the specimens subjected to neutralization and/or home laundering, while FR-CL-PA treated specimens showed opposite results. By using 0.2% and 0.4% of ZnO or nano-ZnO as co-catalyst, the flame spread rate of neutralized and/or laundered test specimens decreased, even the specimens were undergone 10 home laundering cycles. Moreover, flame-retardant-treated cotton specimens had low breaking load and tearing strength resulting from side effects of the crosslinking agent used, while addition of ZnO or nano-ZnO co-catalyst could compensates for the reduction. Furthermore, the free formaldehyde content was dropped when ZnO and nano-ZnO co-catalyst was added in the treatment.

The characteristic properties of carbon nanotubes (CNTs), particularly their heat conduction, electrical conductivity, high modulus of elasticity, high strength, and resistance to chemicals, have resulted in widespread application of CNTs in nanotechnologies. In this study, CNTs were used to impart specific functionality to textiles by printing techniques. To this aim, modified commercial aqueous dispersions of multiwalled CNTs from Nanocyl® were used for preparing special compositions as paste for printing by conventional techniques (screen printing) and as inks for ink-jet printing to bestow the fabric antistatic and antibacterial properties. Taking into account the importance of the dispersion level of CNT in the printing composition from the point of view of antistatic properties, the quality of the CNT dispersion was assessed on the basis of particle size distribution by means of a DLS PSS Nicomp device. Printings were done on two types of woven fabrics: 100% cotton and 30/70% cotton/polyester blend. The CNTs used in printing were found to impart antistatic and antibacterial properties to the printed fabrics. These imparted properties were resistant to repeated washing. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

In this study, 100% cotton woven fabrics having three different patterns are mercerized by chained mercerizing machine. The temperature is kept at 60°C for all applications. Application types and process period are the variables of this experiment. The effects of mercerization process applied on different conditions are examined in terms of color efficiency and degree of whiteness. Fabrics with different patterns are also compared with each other to understand whether fabric patterns are effective in whiteness and color efficiency. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

In this study, titanium dioxide (TiO2) or nano titanium dioxide (nano-TiO2) was used as a cocatalyst in the flame-retardant (FR) formulation of N-methylol dimethylphosphonopropionamide (Pyrovatex CP New, FR), melamine resin [Knittex CHN, crosslinking agent (CL)], and phosphoric acid (PA) for cotton fabrics to improve the treatment effectiveness and minimize the side effects of the treatment. For FR-treated cotton fabrics, the flame extinguished right after removal of the ignition source with no flame spreading. However, after neutralization and/or home laundering, FR–CL-treated specimens failed the flammability test, whereas the opposite results were obtained from FR–CL–PA-treated specimens. A noticeable result was that the TiO2/nano-TiO2 cocatalyst had a significant effect on decreasing the flame-spread rate. Thermal analysis found that the FR-treated specimens without wet posttreatment showed two endothermic peaks representing the phosphorylation of cellulose and acid-catalyzed dehydration. In addition, the treated fabrics showed some new characteristic peaks in their chemical structures; these were interpreted as carbonyl bands, CH2 rocking bands, and CH3 asymmetric and CH2 symmetric stretching. The surface morphology of the FR–CL–PA-treated cotton specimens showed a roughened and wrinkled fabric surface with a high deposition of the finishing agent that had a lower breaking load and tearing strength, which resulted from the side effects of the CL used. However, the addition of a TiO2 or nano-TiO2 cocatalyst could compensate for the reduction in the tensile strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Piassava (Attalea funifera) fibers subjected to several surface chemical treatments and as-received raw fibers were compared with respect to their thermal and tensile behaviors. The thermal degradation of the raw fibers was characterized by three main stages that corresponded to water release at low temperatures, decomposition of hemicellulose, and decomposition of α cellulose. Mercerization acted mainly on hemicellulose removal, and there was no change in the hydrophilic behavior of the fibers. The removal of hemicellulose split the fibers into microfibrils and favored the thermal decomposition of α cellulose. The same behavior was observed when the fibers were subjected to mercerization and acetylation. The fibers subjected to only acetylation showed thermal behavior similar to that of the raw fibers. With the acetylation treatment, a minor decrease in the hydrophilic character of the fibers was noted. Despite some differences in the thermal behavior, the tensile strengths of the raw and treated fibers were statistically equal. Complementary Fourier transform infrared and scanning electron microscopy analysis corroborated the thermogravimetric analysis/differential thermogravimetry results. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Rice straw (Rs)/polypropylene (PP) composites were prepared in the different ratio of 5 : 95, 10 : 90, 15 : 85, 20 : 80, 25 : 75, and 30 : 70 (Rs wt % : PP wt %) by an injection molding process. This work investigated the tensile strength (TS), bending strength (BS), and impact strength (IS) of the composites. From the results, it is observed that Rs20 : PP80 mixture composite showed better performance with mechanical properties (TS = 26.2 MPa, BS = 58 N/mm2, and IS = 1.7 KJ/mm2) among the composites prepared. Two hybrid composites were also fabricated using 20% Rs, 10% seaweed with 70% PP and 20% Rs, 30% seaweed with 70% PP. In between the two hybrid composites, superior mechanical behavior showed by the hybrid composite in ratio of Rs20 : Sw10 : PP70 with enhanced results such as TS = 28 MPa, BS = 68 N/mm2, and IS = 2.5 KJ/mm2. Water uptake, simulating weathering, and soil degradation test of different composites were also performed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

A 1,2,3,4-butanetetracarboxylic acid (BTCA)–sodium hypophosulfite (SHP) wrinkle-resistance system played an important role in improving the wrinkle-resistance properties of cotton fibers. In this study, titanium dioxide (TiO2) was used as a cocatalyst to further enhance the wrinkle-resistance properties of BTCA–SHP-treated cotton fabrics, that is, those treated with (1) 5% BTCA and 10% SHP; (2) 5% BTCA, 10% SHP, and 0.1% TiO2; and (3) 5% BTCA, 10% SHP, and 0.2% TiO2. In addition, the effect of plasma as a pretreatment process on the wrinkle-resistance properties of the three treatment systems was also studied. The experimental results reveal that the wrinkle-resistance properties of cotton fibers were improved after different wrinkle-resistance treatments. In addition, the plasma pretreatment further enhanced the wrinkle-resistance treatments to different extents, depending on the process parameters. Scanning electron microscopy images confirmed that such plasma pretreatment conditions imparted the best crosslinking effect on the cotton fibers. However, the wrinkle-resistance-treated cotton specimens had lower tensile strength and tearing strength values compared to the control sample, whereas the plasma pretreatment and cocatalyst may have compensated for the reduction in the mechanical strength caused by the wrinkle-resistance agents. In this article, the optimum conditions for the plasma pretreatment on the basis of the result of the wrinkle-recovery angle were analyzed with an L9(3)3 orthogonal array testing strategy technique. The results showed that plasma treatment conditions with (1) a 10 mm/s speed, (2) a 0.1 L/min oxygen flow rate, and (3) a 4-mm jet-to-substrate distance together caused a significant improvement in the wrinkle-resistance properties of the cotton fibers treated with the three different BTCA treatments. Moreover, the treatment speed was the dominant factor, followed by jet-to-substrate distance and oxygen flow rate, in affecting the extent of improvement. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011