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The world of lubricants is driven by the constant pursuit of improved performance in response of the requests of new engine generations. Engine oils play a critical role as lubricants in mitigating wear, reducing friction and ensuring optimal engine operation under diverse conditions. Modern commercial engine oils are complex formulations, comprising of a base oil, generally coming from petroleum sources, formulated with specific, important additives able to optimize the viscosity, thickening and shear stress in the operating temperature range. Such additives are produced in the thousand tons per year scale range. The most important class of additives for modern lubrication is made of organic polymers with variable architectures and topologies, generally referred as “viscosity modifiers” (VMs): they act as “moderators” of viscosity at different working temperatures. The tremendous advances in polymer science have been reflected in the realm of VMs, allowing the commercialization of products obtained by controlled polymerization techniques, and the experimentation of a broad variety of different macromolecular architectures and topologies as VMs. In this review we introduce the reader, together with the basic principles of viscosity modification and thermal‐dependent rheological response, to the fascinating chemistry towards the improvement of VMs, through optimization of macromolecular design and architecture. [ABSTRACT FROM AUTHOR]

With their distinct star architecture, star polymers show some desirable materials properties and have received extensive research interest. To date, the advancements in living anionic and controlled radical polymerization techniques have empowered the versatile synthesis of a variety of star polymers from several groups of monomers that are amenable to these polymerization techniques. Despite the fact that polyethylene is the largest produced commodity polymer worldwide, the synthesis of star polyethylenes as a unique polyethylene grade has somehow lagged due to the limited availability of powerful transition metal catalysts that can effectively facilitate 'living' ethylene polymerization for the construction of star architectures. Nevertheless, some progress had been made over the past two decades. In this review, we attempt to summarize the developments in the area, with an emphasis on synthesis strategies. [ABSTRACT FROM AUTHOR]

Emulsion polymerization is the method of choice to produce a wide range of specialty waterborne polymer dispersions. These are multicharacteristic products that should meet conflicting application properties and are produced through a very complex process prone to suffer run‐to‐run irreproducibilities. In a scenario of increasing competition and smaller margins, achieving even more efficient production of better materials in a consistent, cost effective, safe, and environmentally friendly way will only be possible by implementing on‐line control. However, on‐line control is hindered by the lack of sensors able to monitor most of the characteristics of the emulsion polymers. This perspective discusses the state‐of‐the‐art of the on‐line control of emulsion polymerization reactors highlighting the achievements, challenges, and opportunities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Henry's constant is obtained from the results of Self-Consistent field calculations to compare the surface affinity of amphiphilic copolymers of various architectures. • Spatial distribution of adsorbing segments along polymer chains has great influence on their adsorption and ultimately on colloidal stabilising properties, when used as dispersants. • For star-like polymers with identical chemical compositions, the surface affinity decreases with increasing number of arms. • For amphiphilic copolymers of the same chemical composition, dendritic polymers have the highest surface affinity. Polymer architecture is known to have significant impact on its adsorption behaviour. Most studies have been concerned with the more concentrated, "close to surface saturation" regime of the isotherm, where complications such as lateral interactions and crowding also additionally affect the adsorption. We compare a variety of amphiphilic polymer architectures by determining their Henry's adsorption constant (k H), which, as with other surface active molecules, is the proportionality constant between surface coverage and bulk polymer concentration in a sufficiently dilute regime. It is speculated that not only the number of arms or branches, but also the position of adsorbing hydrophobes influence the adsorption, and that by controlling the latter the two can counteract each other. The Self-consistent field calculation of Scheutjens and Fleer was implemented to calculate the adsorbed amount of polymer for many different polymer architectures including linear, star and dendritic. Using the adsorption isotherms at very low bulk concentrations, we determined the value of k H for these. It is found that the branched structures (star polymers and dendrimers) can be viewed as analogues of linear block polymers based on the location of their adsorbing units. Polymers containing consecutive trains of adsorbing hydrophobes in all cases showed higher level of adsorption compared to their counterparts, where the hydrophobes were more uniformly distributed on the chains. While increasing the number of branches (or arms for star polymers) also confirmed the known result that the adsorption decreased with the number of arms, this trend can be partially offset by the appropriate choice of the location of anchoring groups. [ABSTRACT FROM AUTHOR]

Asymmetric miktoarm star polymers comprising an unequal number of chemically-distinct blocks connected at a common junction produce unique material properties, yet existing synthetic strategies are beleaguered by complicated reaction schemes that are restricted in both monomer scope and yield. Here, we introduce a new synthetic approach coined "μSTAR" - Miktoarm Synthesis by Termination After Ring-opening metathesis polymerization - that circumvents these traditional synthetic limitations by constructing the block-block junction in a scalable, one-pot process involving (1) grafting-through polymerization of a macromonomer followed by (2) in-situ enyne-mediated termination to install a single mikto-arm with exceptional efficiency. This modular μSTAR platform cleanly generates AB n and A(BA') n miktoarm star polymers with unprecedented versatility in the selection of A and B chemistries as demonstrated using many common polymer building blocks: poly(siloxane), poly(acrylate), poly(methacrylate), poly(ether), poly(ester), and poly(styrene). The average number of B or BA' arms (n) is easily controlled by the molar equivalents of macromonomer relative to Grubbs catalyst in the initial ring-opening metathesis polymerization step. While these materials are characterized by dispersity in n that arises from polymerization statistics, they self-assemble into mesophases that are identical to those predicted for precise miktoarm stars as evidenced by small-angle X-ray scattering experiments and self-consistent field theory simulations. In summary, the μSTAR technique provides a significant boost in design flexibility and synthetic simplicity while retaining the salient phase behavior of precise miktoarm star materials.

[Display omitted] • Polymer brush grafted films with different architectures were synthesized. • Combined method of electrodeposition and SI-PET-RAFT polymerization was employed. • Thickness, morphology, absorptivity, and electrochemistry of the films were studied. • Hyperbranched polymers exhibit compactness and ability to passivate brush gaps. • Hyperbranched polymer brushes are promising as protective thin coatings. Hyperbranched polymers, not only possess higher functionality, but are also easier to prepare compared to dendrimers and dendric polymers. Combining electrodeposition and surface-initiated photoinduced electron transfer-reversible addition-fragmentation chain transfer (SI-PET-RAFT) polymerization is hypothesized to be a novel strategy for preparing hyperbranched polymer films on conductive surfaces without degassing. Polymer brush grafted films with four different architectures (i.e. linear, branched, linear- block -branched, and branched- block -linear) were prepared on gold-coated glass substrates using electrodeposition, followed by SI-PET-RAFT polymerization. The resulting film structure and thickness, surface topology, absorption property, and electrochemical behavior were confirmed by spectroscopy, microscopy, microbalance technique, and impedance measurement. These hyperbranched polymer brushes were capable of forming a thicker but more uniformly covered films compared to linear polymer brush films, demonstrating that hyperbranched polymer films can be potentially useful for fabricating protective polymer coatings on various conductive surfaces. [ABSTRACT FROM AUTHOR]

Solvent-free polymer-based electrolytes (SPEs) have gained significant attention to realize safer and flexible lithium-ion batteries. Among all polymers used for preparing SPEs electrolytes, poly(ethylene oxide), a biocompatible and biodegradable polymer, has been the most prevalent one mainly because of its high ionic conductivity in the molten state, the capability for the dissolution of a wide range of different lithium salts as well as its potential for the environmental health and safety. However, linear PEO is highly semicrystalline at room temperature and thus exhibits weak mechanical performance. Addition of nanoparticles enhances the mechanical strength and effectively decreases the crystallization of linear PEO, yet enhancement in mechanical performance often results in decreased ionic conductivity when compared to the neat linear PEO-based electrolytes; new strategies for decoupling ionic conductivity from mechanical reinforcement are urgently needed. Herein, we used lithium bis(trifluoromethane-sulfonyl)-imide (LiTFSI) salts dissolved in various nonlinear PEO architectures, including stars (4-arms and 8-arms) and hyperbranched matrices, and SiO2 nanoparticles (approximately equal to 50 nm diameter) as fillers. Compared to the linear PEO chains, the room temperature crystallinity was eliminated in the branched PEO architectures. The electrolytes with good dispersion of the nanoparticles in the nonlinear PEOs significantly enhanced ionic conductivity, specifically by approximately equal to 40% for 8-arm star, approximately equal to 28% for 4-arms star, and approximately equal to %16 for hyperbranched matrices, with respect to the composite electrolyte with the linear matrix. Additionally, the rheological results of the SPEs with branched architectures show more than three orders of magnitude enhancement in the low-frequency moduli compared to the neat linear PEO/Li systems. The obtained results demonstrate that the solvent-free composite electrolytes made of branched PEO architectures can be quite promising especially for irregularly shaped and environmentally benign battery applications suitable for medical implants, wearable devices, and stretchable electronics, which require biodegradability and biocompatibility. [ABSTRACT FROM AUTHOR]

Sugar-based polymers have been extensively explored as a means to increase drug delivery systems' biocompatibility and biodegradation. Here,we review he use of sugar-based polymers for drug delivery applications, with a particular focus on the utility of the sugar component(s) to provide benefits for drug targeting and stimuli responsive systems. Specifically, numerous synthetic methods have been developed to reliably modify naturally-occurring polysaccharides, conjugate sugar moieties to synthetic polymer scaffolds to generate glycopolymers, and utilize sugars as a multifunctional building block to develop sugar-linked polymers. The design of sugar-based polymer systems has tremendous implications on both the physiological and biological properties imparted by the saccharide units and are unique from synthetic polymers. These features include the ability of glycopolymers to preferentially target various cell types and tissues through receptor interactions, exhibit bioadhesion for prolonged residence time, and be rapidly recognized and internalized by cancer cells. Also discussed are the distinct stimuli-sensitive properties of saccharide-modified polymers to mediate drug release under desired conditions. Saccharide-based systems with inherent pH- and temperature-sensitive properties, as well as enzyme-cleavable polysaccharides for targeted bioactive delivery, are covered. Overall, this work emphasizes inherent benefits of sugar-containing polymer systems for bioactive delivery.

Multiblock (segmented) copoly(urethane–imides) were prepared using as monomers toluene 2,4-diisocyanate-terminated aliphatic polyether and polyester [poly(propylene glycol), poly(1,6-hexanediol/neopentylene glycol-alt-adipic acid)], aromatic diamines [1,4-bis(4'-aminophenoxy)biphenyl sulfone or 4,4'-bis(4''-aminophenoxy)biphenyl in a mixture with 3,5-diaminobenzoic acid], and 1,3-bis(3',4-dicarboxyphenoxy)benzene dianhydride. Each of the polymers contains two structurally different soft polyether/polyester segments and two identical hard imide segments, into one of which the reactive carboxy group is introduced. The covalent cross-linking of the copolymers was performed by the reactions of the carboxy groups with aromatic diisocyanates (toluene 2,4-diisocyanate, biphenylmethane 4,4'-diisocyanate) and 1,2,5,6-diepoxycyclooctane. The cross-linked polymer systems obtained were studied by thermal gravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. The kind of cross-linking agent influences the properties of cross-linked copoly(urethane–imides). Variation of the mechanical loss tangent tan δ and width of the temperature interval of the transition from glassy to rubber-elastic state in relation to the chemical structure of copoly(urethane–imides) was analyzed. For the polymers under consideration, the maximal tan δ values exceed 0.3, which indicates that these polymers exhibit the damping ability. [ABSTRACT FROM AUTHOR]

We explored the mechanochemical degradation of bottlebrush and dendronized polymers in solution (with ultrasonication, US) and solid states (with ball‐mill grinding, BMG). Over 50 polymers were prepared with varying backbone length and arm architecture, composition, and size. With US, we found that bottlebrush and dendronized polymers exhibited consistent backbone scission behavior, which was related to their elongated conformations in solution. Considerably different behavior was observed with BMG, as arm architecture and composition had a significant impact on backbone scission rates. Arm scission was also observed for bottlebrush polymers in both solution and solid states, but only in the solid state for dendronized polymers. Motivated by these results, multi‐mechanophore polymers with bottlebrush and dendronized polymer architectures were prepared and their reactivity was compared. Although dendronized polymers showed slower arm‐scission, the selectivity for mechanophore activation was much higher. Overall, these results have important implications to the development of new mechanoresponsive materials. [ABSTRACT FROM AUTHOR]

The use of labile covalent bonds such as oximes and acetals for their application in the synthesis, and controlled triggered deconstruction, of molecular polymer brushes (MPBs) is reported. Macromonomers (MMs) are produced via reversible addition‐fragmentation chain transfer (RAFT) polymerization using chain transfer agents (CTAs) featuring customized labile moieties. Ring‐opening metathesis polymerization (ROMP) of the MMs using the grafting‐through approach produced MPBs in which the cleavable CTA is incorporated along the backbone, between the brush mainchain and its side chains. Degradation (i.e., the detachment of side chains) of the brush is possible through exposure to an acid stimulus. Especially, ketoxime, solketal, and ethoxyethyl (EE) acetal‐based motifs demonstrate excellent orthogonality to the polymerization protocols. This study highlights how polymer architectures can be built from, and reverted to, single polymer chains by using well‐designed CTAs in a straight‐forward approach. [ABSTRACT FROM AUTHOR]

Empty fruit bunches are a lignocellulosic waste byproduct of palm oil production. As is typical for many such fibres from a waste stream, the utilization of these fibres as material, or source of carbon for the production of bioethanol, is hampered by a poor knowledge of the solid state polymer nanostructure where a long fibrous crystalline polymer is embedded in an amorphous matrix. In this study we characterize the bionanocomposite structure, long fibrous cellulose crystals in an amorphous matrix, with X-ray scattering and solid state NMR of empty fruit bunches. Our aim is to provide a structural basis to understand the processing of fibres and their degradation. X-ray scattering both at small and wide angles provided a complementary perspective on the fundamental unit of cellulose organization, long fibrous crystallites called microfibrils: the spiral angle of microfibrils around fiber axis; and the organization of individual cellulose chains in the crystallites. Solid state NMR provides structural and compositional perspectives on the amorphous component. Some general comments on the complementary use of these two techniques in biofibers are given. [ABSTRACT FROM AUTHOR]

Dendritic polymers have highly branched three‐dimensional architectures, the fourth type apart from linear, cross‐linked, and branched one. They possess not only a large number of terminal functional units and interior cavities, but also a low viscosity with weak or no entanglement. These features endow them with great potential in various biomedicine applications, including drug delivery, gene therapy, tissue engineering, immunoassay and bioimaging. Most review articles related to bio‐related applications of dendritic polymers focus on their drug or gene delivery, while very few of them are devoted to their function as cancer diagnosis agents, which are essential for cancer treatment. In this review, we will provide comprehensive insights into various dendritic polymer‐based cancer diagnosis agents. Their classification and preparation are presented for readers to have a precise understanding of dendritic polymers. On account of physical/chemical properties of dendritic polymers and biological properties of cancer, we will suggest a few design strategies for constructing dendritic polymer‐based diagnosis agents, such as active or passive targeting strategies, imaging reporters‐incorporating strategies, and/or internal stimuli‐responsive degradable/enhanced imaging strategies. Their recent applications in in vitro diagnosis of cancer cells or exosomes and in vivo diagnosis of primary and metastasis tumor sites with the aid of single/multiple imaging modalities will be discussed in great detail. This article is categorized under:Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic DiseaseDiagnostic Tools > in vivo Nanodiagnostics and ImagingDiagnostic Tools > in vitro Nanoparticle‐Based Sensing [ABSTRACT FROM AUTHOR]

C1 polymerizations enable the synthesis of densely functionalized, persubstituted polymers that are challenging to access using conventional methods. One class of C1 polymers are the poly(carbyne)s, which are unique in that they can adopt branched or linear structures, or combinations thereof. Herein, we report the synthesis of new poly(carbyne)s, including those that feature side chains with carbonyl‐containing functional groups. The polymers were obtained by exposing solutions of monomers outfitted with trihalomethyl or trimethyl orthoformate groups to metallic lithium, and reaction performance was improved when electron transfer agents (e.g. naphthalene) were included. The mechanisms of the polymerizations were also deconvoluted and found to depend on the monomer employed. [ABSTRACT FROM AUTHOR]

One of the main limitations of protein drugs is their restricted capacity to cross biological barriers. We have previously reported nanostructured complexes of insulin and modified octaarginine (C12-r8), enveloped by a polyethyleneglycol-polyglutamic acid (PEG-PGA) protective shell, and showed their capacity to overcome different barriers associated to the oral modality of administration. The objective of this work was to produce the said nanocomplexes with structurally diverse PEG-PGA shells, i.e. with different chain lengths and PEG substitution degrees, and comparatively analyze their PEG surface density and subsequent impact on their interaction with mucus glycoproteins and Caco-2 cells. The new PEG-PGA enveloped C12-r8-insulin nanocomplexes (ENCPs) exhibited a narrow size distribution (average size of 210–239 nm), a neutral surface charge and a 100% insulin association efficiency (final insulin loading of 16.5–29.6% w/w). Proton nuclear magnetic resonance (1H NMR) analysis indicated the possibility to modulate the PEG density on the ENCPs from 6.7 to 44.5 PEG chains per 100 nm2. This increase in the ENCPs PEG surface density resulted in their reduced interaction with mucins in vitro, while their interaction with Caco-2 cells in vitro remained unaltered. Overall, these data indicate the capacity to tune the surface characteristics of the ENCPS in order to maximize the capacity of these nanocarriers to overcome barriers associated to mucosal surfaces. [ABSTRACT FROM AUTHOR]

Tandem mass spectrometry (MS2) has been employed to elucidate the topology and branching architecture of star-branched polyethers. The polymers were ionized by matrix-assisted laser desorption/ionization (MALDI) to positive ions and dissociated after leaving the ion source via laser-induced fragmentation. The bond scissions caused under MALDI-MS2 conditions occur preferentially near the core-branch joining points due to energetically favorable homolytic and heterolytic bond cleavages near the core and release of steric strain and/or reduction of crowding. This unique fragmentation mode detaches complete arms from the core generating fragment ion series at the expected molecular weight of each branch. The number of fragment ion distributions observed combined with their mass-to-charge ratios permit conclusive determination of the degree of branching and the corresponding branch lengths, as demonstrated for differently branched homo- and mikto-arm polyether stars synthesized via azide-alkyne click chemistry. The results of this study underscore the utility of MS2 for the characterization of branching architecture and branch lengths of (co) polymers with two or more linear chains attached to a functionalized central core. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract This study shows how highly branched poly(N -isopropyl acrylamide) (HB-PNIPAM) with a chain pendant solvatochromic dye (Nile red) could provide a fluorescence signal, as end groups bind to bacteria and chain segments become desolvated, indicating the presence of bacteria. Vancomycin was attached to chain ends of HB-PNIPAM or as pendant groups on linear polymers each containing Nile red. Location of the dye was varied between placement in the core of the branched polymer coil or the outer domains. Both calorimetric and fluorescence data showed that branched polymers responded to binding of both the peptide target (D-Ala-D-Aa) and bacteria in a different manner than analogous linear polymers; binding and response was more extensive in the branched variant. The fluorescence data showed that only segments located in the outer domains of branched polymers responded to binding of Gram-positive bacteria with little response when linear analogous polymer or branched polymer with the dye in the inner core was exposed to Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Abstract We consider a binary mixture of two polymers with different architecture, consisting of linear and cyclic chains. We study this system by performing extensive molecular dynamics computer simulations of bead-spring models, which possess the open-chain and loop topology. The system is confined between two walls, and we consider both the case of attractive- and repulsive polymer-wall interactions. By changing the chain length of the two polymers so as to encompass two regimes with low and high degree of polymerization, we show the effect on the structural properties at the interface. Our results provide some physical insight on the competition between polymer architecture and chain length in determining the surface adsorption. [ABSTRACT FROM AUTHOR]

Highlights • RAFT polymerization was applied to generate architecturally defined KHIs. • Linear and branched PNIPAM were fully evaluated while varying the cooling rate. • Our results suggest a possible new mechanism for managing hydrate formation with a branched PNIPAM. • This study provided a better understanding of the architecture-property effect on hydrate prevention. Abstract As the oil and gas industry produces hydrocarbons from deeper waters and colder regions the issue of hydrate formation becomes more serious. As a result, hydrate inhibition has focused on kinetic hydrate inhibitors (KHI) and anti-agglomerants (AA) as an alternative to the existing approaches which involves injecting vast quantities of thermodynamic inhibitors. In this research, we evaluated the effect of different architectures (linear and branched) of poly(N -isopropylacrylamide) (PNIPAM) polymers synthesized using reversible addition−fragmentation chain-transfer (RAFT) polymerization. Unlike non-reversible deactivation radical polymerisation (RDRP) synthetic routes this generates accurately controlled KHI candidates with target molecular weight, narrow molecular weight distributions and controlled architecture, so that the effect on hydrate inhibition can be more accurately assessed. The RAFT-based polymers (linear and branched) were compared to a commercially available linear PNIPAM synthesized via non-RDRP radical polymerization and control groups (pure water, PVP, and Luvicap). The hydrate experiments were performed in a high pressure autoclave with continuous cooling under different cooling rates (0.25 K/min, 0.033 K/min, and 0.017 K/min). In addition, a cold restart was simulated using constant subcooling. The results regarding subcooling temperature, onset time, and hydrate fraction with resistance-to-flow were compared to known KHIs. These revealed that a linear PNIPAM-MacroRAFT polymer delayed the hydrate nucleation with similar performance to known KHIs (eg., PVP and Luvicap). However, a branched polymer showed the best performance in terms of hydrate fraction and resistance-to-flow among all of the systems tested in this study. These data provide valuable information regarding linear and branched PNIPAM-MacroRAFT polymers by demonstrating their ability to delay hydrate formation but also in preventing hydrate agglomeration. These findings confirm that polymer architecture can effect hydrate inhibition. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Ionic liquids are a class of materials with unique physicochemical properties and intriguing preorganized and tunable solvent structures. Recent usage of ionic liquids as precursors, templates, and solvents has led to polymeric materials with tailored sizes, dimensionalities, morphologies, and functionalities that are difficult to achieve by employing common organic solvents. Ionic liquid monomers from unique macromolecules—known as poly(ionic liquid)s or polymerized ionic liquids—that incorporate cationic and/or anionic sites either pendant to or within the polymer backbones. Poly(ionic liquid)s have recently attracted increasing interest across a wide range of applications, e.g., thermo-responsive materials, carbon materials, catalysis, porous polymers, separation and absorption materials, and energy harvesting and generation as well as biological applications. This review presents a literature survey of recent work on three-dimensional (3D) printing technology over the past few years, highlighting the unique features of ionic liquids and poly(ionic liquid)s in emerging applications of 3D printing. Finally, we provide an overview of several development opportunities that could lead to new advancements in this exciting research field. [ABSTRACT FROM AUTHOR]

Phenol removal and recovery from wastewaters are highly demanded in industries due to its high toxicity and industrial importance. It can transport through the silicon-based rubber polydimethylsiloxane (PDMS) via the solution-diffusion mechanism. To improve the phenol removal efficiency in extractive processes, dense PDMS membranes with different macromolecular structures have been developed and evaluated in this work. The condensation-cured PDMS membranes (PA) with network architecture exhibited higher phenol partition coefficients ( K ) than the hydrosilylation-cured PDMS membranes with linear and branch architectures. This was attributed to the four-armed quaternary-siloxy linkages formed in the three-dimensional network structure, increasing the free volume for phenol passage and hydrogen bonding between phenol and PDMS matrix. The K of PA was further enhanced by optimizing the PDMS precursor chain length and cross-linker amount, and the corresponding membrane mechanical properties and phenol overall mass transfer coefficients ( k 0 ) were examined. The optimal PA formulation was utilized to fabricate a highly effective nanofibrous composite membrane via spray coating. The resultant composite membrane exhibited a k 0 of 18.3 ± 1.3 × 10 −7 m/s in an aqueous-aqueous extractive process, significantly outperforming the commercial counterpart with 45% increment. This is the first demonstration of the importance of PDMS macromolecular structures on phenol extraction. The newly-developed condensation-cured PDMS could contribute to the fabrication of highly effective composite membranes for various extractive processes. [ABSTRACT FROM AUTHOR]

In this study, poly( ε -caprolactone)-co-poly(ethylene glycol) copolymers grafted with a cationic ligand, propargyltrimethyl ammonium iodide (PTA), to fabricate the cationized triblock (P(CatCLCL) 2 -PEG) and diblock (P(CatCLCL)-mPEG) copolymers were investigated their potential use for oral delivery of enoxaparin (ENX). Influences of various PTA contents and different structures of the copolymers on molecular characteristics, ENX encapsulation, particle characteristics, and capability of drug transport across Caco-2 cells were elucidated. The results showed that P(CatCLCL) 2 -PEG and P(CatCLCL)-mPEG copolymers self-aggregated and encapsulated ENX into spherical particles of ∼200–450 nm. The increasing amount of PTA on the copolymers increased encapsulation efficiency of over 90%. The ENX release from both types of the cationized copolymer particles was pH-dependent which was retarded at pH 1.2 and accelerated at pH 7.4, supporting the drug protection in the acidic environment and possible release in the blood circulation. The toxicity of ENX-loaded particles on Caco-2 cells decreased when decreasing the amount of PTA. The triblock and diblock particles dramatically enhanced ENX uptake and transport across Caco-2 cells as compared to the ENX solution. However, the different structures of the copolymers slightly affected ENX transport. These results suggested that P(CatCLCL) 2 -PEG and P(CatCLCL)-mPEG copolymers would be potential carriers for oral delivery of ENX. Statement of Significance The anionic drugs such as proteins, peptides or polysaccharides are generally administered via invasive route causing patient incompliance and high cost of hospitalization. The development of biomaterials for non-invasive delivery of those drugs has gained much attention, especially for oral delivery. However, they have limitation due to non-biocompatibility and poor drug bioavailability. In this study, the novel poly( ε -caprolactone)-co-poly(ethylene glycol) copolymers grafted with propargyltrimethyl ammonium iodide, a small cationic ligand, were introduced to use as a carrier for oral delivery of enoxaparin, a highly negatively charged drug. The study showed that these cationized copolymers could achieve high enoxaparin entrapment efficiency, protect drug release in an acidic environment and enhance enoxaparin permeability across Caco-2 cells, the intestinal cell model. These characteristics of the cationized copolymers make them a potential candidate for oral delivery of anionic drugs for biomaterial applications. [ABSTRACT FROM AUTHOR]