Copolymer Poly Research Articles

Unraveling the modulation art of ordered nanomesh-like hydration product on fiber-cement interfaces: Insights from fishing net inspiration

The morphology of interface hydration products is crucial as it directly determines the interface mechanics. Inspired by the fishing nets, we employed photo-grafted active copolymer Poly(vinylpyrrolidone-co-acrylic acid) on the inert glass fibers. Providing a template for PVP-co-PAA maintains its regulatory capability in cement paste. For the first time, ordered nanomesh-like hydrated calcium silicate (CSH) with average pore diameter of 30 nm are developed in cement paste. The interface strength and energy absorption increased by 90 % and 253 %, respectively. XPS and SEM revealed that the multi-scale regulation mechanisms originated from the preferential adsorption and stable dispersion of Ca2+ result from the strong electronegativity and steric hindrance of pyrrolidone rings. CSH nuclei (60 nm) dispersed well on fiber templates, stacked along fiber surfaces, without collapse or tilt, intertwined into nanomesh. Nanomesh-like CSH in cement paste holds significant potentials for the improvement of mechanical properties of fiber-cement interfaces, contributing to construction sustainability.

Design and Experimental Characterization of a Microfluidic Piezoelectric Pump Utilizing P(VDF-TrFE) Film

Advancements in wearable technology and lab-on-chip devices necessitate improved integrated microflow pumps with lower driving voltages. This study examines a piezoelectric pump using a flexible β-phase copolymer poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) film. Six samples (S1–S6) were fabricated and subjected to a three-step annealing process to optimize their properties. Characterization was conducted via atomic force microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, impedance analysis, and polarization hysteresis loop measurements. The results show that annealing at approximately 135 degrees Celsius produces a β-phase structure with uniform “rice grain”-like crystallites. A microfluidic pump with a nozzle/diffuser structure, using S4 film as the drive layer, was designed and manufactured. Diaphragm deformation and pump performance were assessed, showing a maximum water flow rate of 25 µL/min at 60 Hz with a peak-to-peak voltage (Vpp) of 60 V. The flow rate could be precisely controlled within 0–25 µL/min by adjusting the Vpp and frequency. This study effectively reduced the driving voltage of the piezoelectric pump, showing that it has significant implications for smart wearable devices.

Smart Crowding on pH-Induced Elasticity of Weakly Anionic poly(N-Isopropylacrylamide)-Based Semi-Interpenetrating Polymer Networks via Integration of Methacrylic Acid and Linear Polyacrylamide Chains.

Weakly anionic semi-interpenetrating polymer networks (semi-IPNs), comprised of copolymer poly(N-isopropylacrylamide-co-methacrylic acid) P(NIPA-MA) and linear poly(acrylamide) (LPA) chains as macromolecular crowding agent, are designed to evaluate pH-induced swelling and elasticity. Uniaxial compression testing after swelling in various pH-conditions is used to analyze the compressive elasticity as a function of swelling pH and LPA-content. The swelling of P(NIPA-MA)/LPA semi-IPNs is strongly pH-dependent due to MA units incorporated into the copolymer network which already exhibits temperature-sensitivity by presence of PNIPA counterpart. Since the behavior of semi-IPNs is a combination of PMA, LPA, and PNIPA moieties, the sensitivity of swelling to external pH can be modified with increasing swelling temperature. At high pH conditions, LPA-doped semi-IPNs show elasticity representing soft and loosely cross-linked structure. Elastic modulus is higher in acidic pH condition due to the less swelling tendency, while in basic pH, the modulus decreases significantly in coordination with swelling. Oscillatory swelling reveals how fast semi-IPNs can respond to environmental pH change (2.1-10.7). By describing adsorption potential of semi-IPNs for cationic methylene blue uptake by pseudo-first-order and Freundlich model, the designed poly(NIPA-MA)/LPA semi-IPNs emerge as promising smart materials in applications requiring rapid response to changes in temperature and pH via diffusional properties.

Antimicrobial Peptide SAAP-148-Functionalized Hydrogels from Photocrosslinkable Polymers with Broad Antibacterial Activity.

Antimicrobial peptides (AMPs) are promising alternatives to traditional antibiotics for treating skin wound infections. Nonetheless, their short half-life in biological environments restricts clinical applicability. Covalent immobilization of AMPs onto suitable substrates offers a comprehensive solution, creating contact-killing surfaces with long-term functionality. Here, a copolymer of poly[(hydroxy ethyl acrylamide)-co-(4-benzophenone acrylamide)-co-(pentafluorophenyl acrylate)-co-(ECOSURF EH-3 acrylate)], in short poly(HEAAm-co-BPAAm-co-PFPA-co-EH3A), is synthesized by free radical polymerization. Subsequent modification of active ester groups with the amine groups of SAAP-148, results in a copolymer, that is non-cytotoxic to human lung fibroblasts. UV photocrosslinking of the benzophenone units yields a polymer network that forms a hydrogel after swelling with aqueous medium. Both the SAAP-148-modified polymer in solution and the photocrosslinked hydrogels show good antimicrobial activity against strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, including multidrug-resistant strains, frequently found in wound infections. The covalent attachment of SAAP-148 prevents leaching, ensuring sustained antimicrobial activity for at least 48 h in diluted human blood plasma and 14 days in PBS. This prolonged retention of antimicrobial activity in human blood plasma significantly enhances its clinical potential. Overall, this study shows the potential of the AMP-functionalized photocrosslinkable polymer as antimicrobial wound dressings, providing an effective alternative to antibiotics.

Preparation and Characterization of Quick‐Setting Poly Cyanoacrylate Foams

ABSTRACTThe primary aim of this project is to develop ultra‐high expansion and quick‐setting foams using poly (ethyl cyanoacrylate), poly (butyl cyanoacrylate), and poly (co‐ethyl‐butyl) cyanoacrylate. To achieve this, poly cyanoacrylate foams were created under various conditions, utilizing different monomers, initiators, foaming agents/solvents, and compositions. Several properties of the foams were assessed, including formation and expansion rates, mechanical strength, moisture absorption, thermal resistance, density, and morphology. The findings indicated that, under optimal conditions, the foams made from poly (ethyl cyanoacrylate), poly (butyl cyanoacrylate), and a copolymer of poly (ethyl cyanoacrylate‐co‐butyl cyanoacrylate) exhibited fast expansion times of approximately 0.9, 2, and 1.5 s, respectively. These foams demonstrated an average volume increase of about 35 times, 45 times, and 36 times compared to the raw materials. The average compressive strengths recorded were 6, 3, and 4 kg/cm2, while the average water absorption rates were 5%, 20%, and 7%, respectively.

Ultrasensitive In Vitro and Ex Vivo Tracking of 13C-Labeled PEG-PLA Degradation Products by MALDI-TOF Mass Spectrometry.

Copolymers of poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) are widely used in biomedical applications. As inactive ingredients in formulations, tracking their degradation byproducts in vivo stands as a major challenge but is a pivotal endeavor to ensure safety and further progress in clinical stages. Current bioanalytical methods used to monitor this degradation lack sensitivity and quantification precision. This study introduces a cost-effective synthetic route for 13C-labeled PEG-PLA copolymers, combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), to monitor their in vitro and ex vivo degradation. Incorporating 13C isotopes into copolymers significantly enhances MALDI-TOF sensitivity, allowing for precise detection of degradation products at exceedingly low concentrations. We demonstrate the ability to trace 13C-labeled PEG-PLA in complex biological media (urine, plasma) at concentrations 100 times lower than labeled PEG-PLA. Our results pave the way toward ultrasensitive in vivo tracking and elucidation of in vivo fate of this widely investigated polymer family.

A Comparative Study of Structural Contribution to Biocidability via Immobilization of Fluorinated and Nonfluorinated Quaternary Ammonium Salts on Top Surfaces.

Higher biocidability of fluorinated quaternary ammonium salt (QAS) is usually contributed to its preferential segregation to the surface to better contact with and kill bacteria. However, whether its structure also elicits better performance is still unclear. Herein, the same amount of a fluorinated QAS and its nonfluorinated counterpart are both immobilized on the top surface to eliminate the effect of concentration distribution to only study their structure-biocidability relationship. Briefly, the fluorinated and nonfluorinated QASs were synthesized by quaternization of N,N-dimethylethanolamine with 2-(perfluorooctyl)ethyl bromide that was prepared by bromination of 2-(perfluorooctyl)ethanol and 1-bromodecane, respectively. Polystyrene (PS) and diblock copolymer poly(styrene)-b-poly(tert-butyl acrylate) (PS-PtBA) were successively spin coated on SiO2 wafers at different concentrations to form bilayer structures that have a PS base layer and a PtBA top layer. The tert-butyl acrylate groups of the PtBA layer of 0.9 nm were converted to carboxylic acid groups with trifluoroacetic acid for respective esterification with the two hydroxy-containing QASs. It was observed that the fluorinated and nonfluorinated surfaces fabricated at the maximum comparable esterification yield of 63.5% fully eradicated ∼104 CFU of Staphylococcus aureus and Escherichia coli in 120 and 150 min, respectively, indicating that the fluorocarbon chain is more biocidal through better interpenetration into bacterial membranes. Immobilization of a functionality on top surface provides a universal strategy to study its structural contribution to activity without interference of the concentration distribution.

PH‐sensitive size/surface charge‐adaptive quaternary ammonium salt copolymer micelles for antibiofilm activity against Staphylococcus aureus

AbstractThe low penetration of antibacterial materials within biofilms results in a 1000‐fold decrease in bactericidal efficiency, complicating the complete removal of biofilms and potentially leading to persistent and recurrent bacterial infections that significantly impact human health. In this study, we present a multifunctional pH‐responsive antibacterial material based on random copolymers poly(dimethylaminoethyl methacrylate decyl ammonium bromide‐co‐polyethylene glycol methacrylate) copolymer (PQACs10‐co‐PEGMA10). The PQACs10‐co‐PEGMA10 copolymers could self‐assemble into micelles in selective solvent water. With the stealth function of polyethylene glycol (PEG), the PQACs10‐co‐PEGMA10 micelles can rapidly penetrate biofilms in a physiological environment and exhibit excellent antibacterial activity by exposing the quaternary ammonium salt (QACs) in an acidic microenvironment to eliminate biofilm. Furthermore, PQACs10‐co‐PEGMA10 micelles were applied as coatings using a dropwise method. The PEG chain formed hydration layer and the QACs chain for sterilization can hinders bacterial adhesion and proliferation, thereby preventing biofilm formation. The results show that the minimal inhibit concentration values and minimum biofilm eradication concentrations of the PQACs10‐co‐PEGMA10 micelles against Gram‐positive Staphylococcus aureus were 64 and 128 μg/mL, respectively. The antifouling and antibacterial rates of micelle coating against S. aureus were more than 99.99%. Taken together, the pH‐responsive PQACs10‐co‐PEGMA10 micelles demonstrate a good ability to clear and prevent biofilms, holding promise for complete biofilm removal and a reduction in biofilm‐related infections.

Block copolymer micelles stabilized Pickering emulsions in templating ultralight conducting PEDOT: PSS elastomeric aerogels

Amphiphilic copolymers poly(N-(2-methacryloylxy) ethyl pyrrolidone)-block-poly(2-(perfluorooctyl) ethyl methacrylate) (PNMPm-b-PFMAn) with similar m/n of about 10 preferred to form spherical micelles in water regardless of the molecular weight. These PNMPm-b-PFMAn micelles as Pickering emulsifiers commonly favored the formation of O/W Pickering emulsions in the cyclohexane/water systems, and the corresponding interfacial structures were characterized by the confocal laser scanning microscopy (CLSM) method. Moreover, high internal phase Pickering emulsions (HIPPEs) were formed at high volume ratio of oil/water (VO/VW), which were excellent templates in generating structurally well-defined 3D porous PEDOT:PSS aerogels with low density and high conductivity. It was noticed that the HIPPE-templated PEDOT:PSS aerogels were mainly composed of hierarchically connected nano-/micro-level fibers, which were significantly different from the randomly intertangled lamellar micro-belts of PEDOT:PSS aerogels prepared by the hydrogel method under the same conditions. In addition, the HIPPE-templated stretchable and compressible PEDOT:PSS aerogels showed wide strain-invariant resistance (SIR) range and remarkable cycling stability, which were far superior to the hydrogel ones.

Genome-Centric Metagenomics Insights into the Plastisphere-Driven Natural Degradation Characteristics and Mechanism of Biodegradable Plastics in Aquatic Environments.

Biodegradable plastics (BPs) are pervasively available as alternatives to traditional plastics, but their natural degradation characteristics and microbial-driven degradation mechanisms are poorly understood, especially in aquatic environments, the primary sink of plastic debris. Herein, the three-month dynamic degradation process of BPs (the copolymer of poly(butylene adipate-co-terephthalate) and polylactic acid (PLA) (PBAT/PLA) and single PLA) in a natural aquatic environment was investigated, with nonbiodegradable plastics polyvinyl chloride, polypropylene, and polystyrene as controls. PBAT/PLA showed the weight loss of 47.4% at 50 days and severe fragmentation within two months, but no significant decay for other plastics. The significant increase in the specific surface area and roughness and the weakening of hydrophobicity within the first month promoted microbial attachment to the PBAT/PLA surface. Then, a complete microbial succession occurred, including biofilm formation, maturation, and dispersion. Metagenomic analysis indicated that plastispheres selectively enriched degraders. Based on the functional genes involved in BPs degradation, a total of 16 high-quality metagenome-assembled genomes of degraders (mainly Burkholderiaceae) were recovered from the PBAT/PLA plastisphere. These microbes showed the greatest degrading potential at the biofilm maturation stage and executed the functions by PLA_depolymerase, polyesterase, hydrolase, and esterase. These findings will enhance understanding of BPs' environmental behavior and microbial roles on plastic degradation.

Engineering Shape to Overcome Contraction: The Role of Polymer-Collagen Hybrids in Advanced Dermal Substitutes.

Collagen gels are the standard dermal equivalents par excellence, however the problem of rapid cell-mediated contraction remains unresolved. Therefore, the development of hybrid constructs (HCs) based on collagen and polymeric scaffolds is proposed to address the mechanical instability that usually limits the formation of new, functional tissue. Equally important, these synthetic structures should be temporary (degradable) while ensuring that cells are well-adapted to the new extracellular environment. In this study, we screened a library of scaffolds made of various polymers, including homopolymers of polycaprolactone (PCL) and poly D,L-lactide (PLA50), their blends (PCL/PLA50), and copolymers (poly(D,L-lactide-co-caprolactone), PCLLA50) to prepare HCs in a layer-by-layer fashion. The properties of polymers and copolymers along with their processability by electrospinning and 3D-printing were evaluated. Then, we assessed the HCs resistance toward cell-mediated contraction as well as the degradation of the polymeric scaffolds. Our results indicate that scaffolds with higher PLA50 content (e.g., PLA50 100%, PCL/PLA50 or PCLLA50, both at 50/50 caprolactone-to-D,L-lactide molar ratio) presented more drawbacks in terms of handleability and processing, while those with greater PCL presence showed structural steadiness and ease to use. All the scaffolds integrated well with the collagen gel to form the corresponding HCs. With few exceptions, the HCs demonstrated good resistance to cell-derived contraction over 3 weeks. Notably, HCs based on PCLLA50 90/10 (both versions, electrospun or 3D-printed) performed best, showing only a 5%-17% area reduction compared to the 93% observed in collagen-only gels. This copolymer displayed hydrolytic degradation depending on its shape, with up to 45% and 65% loss of molecular weight for the electrospun and 3D-printed forms, respectively, correlating with their progressive change in mechanical features. HCs containing PCLLA50 90/10 also exhibited a better fibroblast distribution, enhanced myofibroblastic differentiation, and a three-fold increase in cell proliferation (when the electrospun type was used) compared to collagen controls. These findings were instrumental in selecting a potential HC that might be used for future experiments in vivo.

Dependence of the crystal structure on the d-units amount in semi-crystalline poly(lactic acid)

The study investigates the impact of the d-lactic acid units content on the crystallinity and crystal structure of commercial poly(lactic acid) (PLA) grades, which are copolymers of poly(l-lactic acid) (PLLA) containing a minor amount of d-units. As the d-units content increases, a detectable decrease in crystallinity was observed along with a simultaneous rise in mobile amorphous fraction (MAF) and a reduction in rigid amorphous fraction (RAF). The percentage of d-units was found not to significantly affect RAF thickness, suggesting that the d-units are not completely excluded from the crystals. The inclusion of d-units as defects in the PLA crystal lattice was confirmed by XRD analysis, which disclosed that the crystal phase gets gradually richer of d-units as the crystallization time evolves. FT-IR analysis proved that the incorporation of d-units in the crystal phase is promoted by the formation of local CH3···O=C interactions, similar to those massively active between PLLA and poly(d-lactic acid) (PDLA) in the stereocomplex. The establishment of these interactions leads to a contraction of the interplanar distances and a decrease in the crystal cell volume with increasing the crystallization time and the d-units percentage. In summary, the study proves that for PLA copolymers containing a d-units percentage at least up to about 8 %, d-units are included in the crystal lattice.

A lanthanide luminescent sensor doped polymer dots for ratiometric fluorescence detection of hydrogen sulfide

As one of the indexes of food freshness, hydrogen sulfide content is closely related to food spoilage. A dual-emission sensor for H2S detection was reported in this paper. Poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] Polymer dots (MEH-PPV-Pdots) were prepared by copolymer of poly [2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] and styrene-maleic anhydride. The sensor was obtained by embedding purple MEH-PPV-Pdots in a green MOF. The accommodated MEH-PPV-Pdots were considered as the reference signal, while copper ions on the host skeleton served as accessible reaction sites, allowing MEH-PPV-Pdots/Tb0.99Cu0.01-MOF to selectively sense H2S. The sensor exhibited reduced green fluorescence and proportional response to H2S. Because H2S can transfer charge on copper ions and thus affect the green light emitted by rare earth ions. The results showed that the sensor had good stability to H2S in HEPES buffer, fast response, obvious color change, high selectivity and sensitivity. The sensor has been applied to the detection of aquatic products, showing good visualization effect.

Tailoring Hydrogel Sheet Properties through Co-Monomer Selection in AMPS Copolymer Macromers.

This study investigates hydrogels based on 2-Acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPS) copolymers, incorporating N-hydroxyethyl acrylamide (HEA) and 3-sulfopropyl acrylate potassium salt (SPA). The addition of HEA and SPA is designed to fine-tune the hydrogels' water absorption and mechanical properties, ultimately enhancing their characteristics and expanding their potential for biomedical applications. A copolymer of AMPS, 2-carboxyethyl acrylate (CEA) combined with methacrylic acid (MAA) as poly(AMPS-stat-CEA-stat-MAA, PACM), was preliminarily synthesized. CEA and MAA were modified with allyl glycidyl ether (AGE) through ring-opening, yielding macromers with pendant allyl groups (PACM-AGE). Copolymers poly(AMPS-stat-HEA-stat-CEA-stat-MAA) (PAHCM) and poly(AMPS-stat-SPA-stat-CEA-stat-MAA) (PASCM) were also synthesized and modified with AGE to produce PAHCM-AGE and PASCM-AGE macromers. These copolymers and macromers were characterized by 1H NMR, FT-IR, and GPC, confirming successful synthesis and functionalization. The macromers were then photocrosslinked into hydrogels and evaluated for swelling, water content, and mechanical properties. The results revealed that the PASCM-AGE hydrogels exhibited superior swelling ratios and water retention, achieving equilibrium water content (~92%) within 30 min. While the mechanical properties of HEA and SPA containing hydrogels show significant differences compared to PACM-AGE hydrogel (tensile strength 2.5 MPa, elongation 47%), HEA containing PAHCM-AGE has a higher tensile strength (5.8 MPa) but lower elongation (19%). In contrast, SPA in the PASCM-AGE hydrogels led to both higher tensile strength (3.7 MPa) and greater elongation (92%), allowing for a broader range of hydrogel properties. An initial study on drug delivery behavior was conducted using PACM-AGE hydrogels loaded with photosensitizers, showing effective absorption, release, and antibacterial activity under light exposure. These AMPS-based macromers with HEA and SPA modifications demonstrate enhanced properties, making them promising for wound management and drug delivery applications.

Ultrasound-assisted dispersive micro solid phase extraction of maneb in water and food samples with new hybrid block copolymer material prior to micro-spectrophotometric analysis

A simple and effective ultrasound-assisted dispersive micro solid-phase extraction (UA-dμSPE) method was developed for the spectrophotometric determination of traces maneb in food and water. In this study, a new hybrid block copolymer poly (vinyl benzyl chloride-b-dimethyl aminoethyl methacrylate) (Pvb-DMA) was synthesized and characterized using techniques such as FTIR, SEM-EDX. The synthesized Pvb-DMA was used as an adsorbent for the extraction of maneb for first time in this study. The effects of different experimental variables such as pH, adsorbent amount, sample volume, eluent type were optimized. The statistical toll factorial design was applied to estimate the individual and combined impact of parameters on the extraction of maneb. The applicability of different solvents such as acetone, methanol, ethanol, tetrahydrofuran, acetonitrile for maneb recovery from adsorbent was tested. The detection and quantification limits were found to be 3.3 ng mL−1 and 10.0 ng mL−1, respectively. In addition, the preconcentration factor and linear range was obtained 300 and 10–500 ng mL−1. The extraction recovery and relative standard deviation were found to be 95 % and 2.8 %, respectively.

PH-Responsive Block Copolymer Micelles of Temsirolimus: Preparation, Characterization and Antitumor Activity Evaluation.

Renal cell carcinoma (RCC) is the most common and lethal type of urogenital cancer, with one-third of new cases presenting as metastatic RCC (mRCC), which, being the seventh most common cancer in men and the ninth in women, poses a significant challenge. For patients with poor prognosis, temsirolimus (TEM) has been approved for first-line therapy, possessing pharmacodynamic activities that block cancer cell growth and inhibit proliferation-associated proteins. However, TEM suffers from poor water solubility, low bioavailability, and systemic side effects. This study aims to develop a novel drug formulation for the treatment of RCC. In this study, amphiphilic block copolymer (poly(ethylene glycol) monomethyl ether-poly(beta-amino ester)) (mPEG-PBAE) was utilized as a drug delivery vehicle and TEM-loaded micelles were prepared by thin-film hydration method by loading TEM inside the nanoparticles. Then, the molecular weight of mPEG-PBAE was controlled to make it realize hydrophobic-hydrophilic transition in the corresponding pH range thereby constructing pH-responsive TEM-loaded micelles. Characterization of pH-responsive TEM-loaded nanomicelles particle size, potential and micromorphology while its determination of drug-loading properties, in vitro release properties. Finally, pharmacodynamics and hepatorenal toxicity were further evaluated. TEM loading in mPEG-PBAE increased the solubility of TEM in water from 2.6μg/mL to more than 5 mg/mL. The pH-responsive TEM-loaded nanomicelles were in the form of spheres or spheroidal shapes with an average particle size of 43.83 nm and a Zeta potential of 1.79 mV. The entrapment efficiency (EE) of pH-responsive TEM nanomicelles with 12.5% drug loading reached 95.27%. Under the environment of pH 6.7, the TEM was released rapidly within 12h, and the release rate could reach 73.12% with significant pH-dependent characteristics. In vitro experiments showed that mPEG-PBAE preparation of TEM-loaded micelles had non-hemolytic properties and had significant inhibitory effects on cancer cells. In vivo experiments demonstrated that pH-responsive TEM-loaded micelles had excellent antitumor effects with significantly reduced liver and kidney toxicity. In conclusion, we successfully prepared pH-responsive TEM-loaded micelles. The results showed that pH-responsive TEM-loaded micelles can achieve passive tumor targeting of TEM, and take advantage of the acidic conditions in tumor tissues to achieve rapid drug release.

Fabrication of photocurable zwitterionic polymer coatings with enhanced antifouling and lubrication properties for urinary catheter applications

Urinary catheters necessitate a surface with antifouling and lubricating properties in order to mitigate bacterial infection, calculus formation, and tissue trauma. Hydrophilic coating is a promising strategy but suffers from the complications of the manufacturing method as well as the lack of longevity. Herein, we report an antifouling and lubricating hydrophilic coating based on zwitterionic copolymer poly(2-Methacryloyloxyethyl phosphatidylcholine-co-hydroxyethyl methacrylate-co-(Benzoyl)phenyl methacrylate (poly(MPC-co-HEMA-co-BP)) through pre-gel solution spin-coating followed by UV-curing. The poly(MPC-co-HEMA-co-BP (PMHB) coatings possess hygroscopic properties that facilitate the formation of a hydrated layer, thereby leading to friction reduction. Moreover, both antibacterial and protein resistance tests substantiate the exceptional antifouling characteristics exhibited by the PMHB coating. Furthermore, after 7 days of coincubation, the antibacterial rates of PMHB coatings against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Proteus mirabilis (P. mirabilis) are 72.98 %, 75.11 %, and 88.23 %, respectively. Subsequently, PMHB coating reduced the attachment of encrustation in a 7 days artificial urine cycling experiment. This study brings new perspective on designing urinary catheter surfaces with lubricating and antifouling properties.

Moderately halophilic bacterium Halomonas alkalicola strain Ext as a platform for poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer production with fruit peels residues as sole carbon source

Polyhydroxyalkanoates (PHAs) are synthesized by a variety of microorganisms as intracellular storage granules under imbalanced nutrition and excess carbon. Carbon sources are key contributors to the high cost of PHA production, hence the need for exploration of cheap and sustainable raw materials for bacteria fermentation. In the present study, Halomonas alkalicola strain Ext isolated from a hypersaline lake in Kenya was assessed for its ability to utilize fruit peels hydrolysates (FPH) as sole carbon sources for PHA production. Sugars were extracted from dried peels of banana, mango, orange, and pineapple fruits through mechanical pretreatment and dilute acid hydrolysis. Fruit peels pretreated with 3 % H2SO4 at 121℃ were utilized for shake flask fermentation to produce PHAs by Halomonas alkalicola Ext. At optimal C:N ratios of between 20:1 and 30:1, the bacterium could produce up to 0.45±0.03, 0.394±0.12, 0.39±0.05, and 0.28±0.0 g/L of PHAs from hydrolysates of orange peels, mango peels, banana peels, and pineapple peels, respectively. A maximum PHA content of 16.92 % was achieved on orange peels hydrolysates with 4 % substrate loading. Monomer analysis with gas chromatography-mass spectrometry (GC-MS) revealed that the bacterium produced a copolymer Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with 3-hydroxyvalerate (3HV) contents of 5.77 %, 6.08 %, 6.79 %, 6.845 %, for orange peels, pineapple peels, mango peels and banana peels substrates, respectively. The findings of this study suggest that fruit peels waste is a potential feedstock for sustainable production of PHAs by Halomonas alkalicola.

Pickering emulsification of pyrrolidone-based block copolymer aggregates: Effects of copolymer composition and oil

A series of block copolymers poly (N-2-(methacryloyloxy) ethyl pyrrolidone)-b-poly (benzylmethacrylate) (PNMP39-b-PBzMAn) were developed. These amphiphilic copolymers formed diversified aggregates in water, depending on the degree of polymerization n of the PBzMA segment. There presented the n-induced morphological transition from spherical micelles to vesicles via wormlike micelles. Moreover, PNMP39-b-PBzMAn aggregates were excellent dual function emulsifiers, showing similarity with both particles and surfactants simultaneously. The emulsification of PNMP39-b-PBzMAn aggregates was affected significantly by the degree of polymerization n of the PBzMA segment and oil. However, the effect of oil was more remarkable in comparison with that of n, in which the compatibility between oil and the hydrophobic PBzMA segment was critical. In general, O/W and W/O emulsions were formed for oils with poor and good compatibility to the PBzMA segment such as nonpolar alkanes and toluene, respectively. In these cases, PNMP39-b-PBzMAn aggregates were remained in water in the alkane/water systems, whereas they were transferred into the toluene phase according to the similarity-intermiscibility principle. For isopropyl myristate, a polar oil with the intermediate compatibility to the PBzMA segment, PNMP39-b-PBzMAn in water were transferred into the oil phase partially. Accordingly, emulsifiers in water and oil benefit the formation of O/W and W/O emulsions, respectively, as observed in the alkane/water and toluene/water systems. As a result, O/W and W/O emulsions were generated by PNMP39-b-PBzMAn with relatively small and large n, respectively. For PNMP39-b-PBzMAn with the intermediate n, W/O/W multiple emulsions were formed attributing to the synergistic emulsification of PNMP39-b-PBzMAn in water and oil.

Morphology and Emulsification of Poly(N-2-(methacryloyloxy) ethyl pyrrolidone)-b-poly(benzyl methacrylate) Assemblies by Polymerization-Induced Self-Assembly.

In this work, a series of amphiphilic diblock copolymers poly(N-2-(methacryloyloxy) ethyl pyrrolidone)-b-poly(benzyl methacrylate) (PNMP m -b-PBzMA n ) were developed by the dispersion polymerization method in ethanol. The polymerization-induced self-assembly (PISA) behaviors were studied systematically, and a comprehensive structure-property relationship was also established. Two distinct PISA tendencies were observed, which was mainly depended on the polymerization degree m of PNMP segment. When m is small such as 39 and 55, morphological transitions from spherical to vesicle-like assemblies via wormlike ones upon increasing n commonly happen regardless of the solid content. Alternatively, spherical assemblies became the sole morphology for PNMP64-b-PBzMA n block copolymers because of the excellent solvophilicity of the PNMP64 segment. Attributing to the amphiphilicity of PNMP m -b-PBzMA n block copolymers, PNMP m -b-PBzMA n assemblies by PISA are a type of excellent Pickering emulsifiers. These assemblies prefer to stabilize O/W Pickering emulsions as confirmed by the confocal laser scanning microscopy method, and the effects of polymerization degree of PBzMA segment or morphologies of PNMP m -b-PBzMA n assemblies are finite.