New water-soluble copolymers of 2-methacryloyloxyethyl phosphorylcholine for surface modification

New copolymers of 2-methacryloyloxyethyl phosphorylcholine with 2-Deoxy-2-methacrylamido-D-glucose, N-vinylpyrrolidone, and N-vinyl-N-methylacetamide were synthesized and characterized; the obtained copolymers contained 10–50 mol% of phosphorylcholine moieties, and their molecular masses ranged from 1.05 × 10⁵ to 4.40 × 10⁵. Reactivity ratios of the monomers were estimated. Conformational states of the copolymers in aqueous solutions were studied. The synthesized copolymer was grafted onto the surface of carbon fiber biosorbent using γ-radiation.     

Investigating the effect of water-mixing nitrogen atmospheric pressure plasma jet on polyether-ether-ketone and time stability under different conditions

Possessing excellent properties including good biocompatibility, high strength, and stiffness, polyether-ether-ketone (PEEK) has significant application values in medical and industrial fields. However, the relatively poor wettability and low adhesion limit its further applications. Atmospheric pressure plasma jet (APPJ) has been utilized for adjusting PEEK properties, but better hydrophilization effect and time stability after treatment are still urgently needed. In this paper, we employ a water-mixing nitrogen (N₂ H₂O) APPJ to process PEEK, and surface wettability can be effectively improved (contact angle ~18° within 2 min, distance between sample and nozzle outlet: 10 mm) without inducing obvious microstructure damages. Additionally, after storing for 40 days, the sample treated by N₂ H₂O APPJ also possessed better wettability (~54°) compared with that treated by N₂ APPJ (~65°). On the basis of this low-damage and high-efficient modification method, we perform aging experiments under different conditions (different temperatures 25, −10°C; and low vacuum condition: 50 kPa) to determine a relatively optimum storing condition for this method. The experiment results indicate that low temperature and vacuum are conducive to retaining the plasma-induced wettability (~34°). The treatment method and storing conditions for PEEK presented here may facilitate the application of PEEK in various fields.     

卡系费休法测定氯乙烯单体中水含量的影响因素

介绍了卡尔费休法的测定原理,具体分析了采用卡尔费休法测定氯乙烯单体中水含量的影响因素,指出采用闪蒸仪进样器,能有效提高分析结果的准确性和工作效率。     

仿贝壳层状MTM/PVA/ANF复合薄膜的制备及其性能研究

通过水蒸发诱导自组装（A）和真空辅助抽滤（F）及其与离心处理（C）组合4种不同方法制备仿贝壳层状结构的蒙脱土/聚乙烯醇/芳纶纳米纤维（MTM/PVA/ANF）复合薄膜，并采用扫描电子显微镜（SEM）、原子力显微镜（AFM）、热重分析仪（TGA）、紫外分光光度计、动态接触角测试仪和拉伸测试仪对复合薄膜的微观结构、热稳定性、透光率、亲水性和力学性能进行表征。结果表明，不同方法（A、CA、F和CF）制得的复合薄膜都呈明显的层状结构，但复合薄膜的透光率、亲水性和力学性能不同。通过F法制备的复合薄膜具有更高的透光率和更好的疏水性；通过CF法制备的复合薄膜具有最优的力学性能，拉伸强度可达132.4 MPa，而通过A法制备的复合薄膜韧性最佳，断裂伸长率可达11.3%。     

Structure,surface tension,and rheological behaviors of hydrophobically associative polyacrylamides by self-emulsified microemulsion polymerization

Hydrophobically associating copolymers using acrylamide (AM), acrylic acid (AA), and Styrene (St) as comonomers were successfully prepared by self-emulsified microemulsion polymerization, in which low-molecular-weight AM/AA/St copolymers as surfactant and AM as cosurfactant. The structure and chemical composition of AM/AA/St copolymers were characterized by Fourier transform infrared, nuclear magnetic (NMR), and differential scanning calorimeter. The content of PSt in the copolymers is determined by ¹H nuclear magnetic resonance spectra, suggesting that the self-made polymer surfactant can disperse uniformly the St monomers to improve the copolymerization efficiency. Furthermore, the polymerization mechanism of the self-emulsified microemulsion method is explored preliminarily. During the synthesis of the copolymers, the purified copolymer solution is obtained in one step without using a small molecular emulsifier such as sodium dodecyl sulfate, in order to avoid the complicated post-treatment process of the small molecular emulsifier. The copolymers revealed good hydrophobic association properties and low surface tension.     

亲水性PET共混材料的制备及性能研究

以机械共混法制备亲水性聚对苯二甲酸乙二醇酯（PET）共混材料，并通过接触角测定仪、差示扫描量热仪(DSC)和电子万能材料试验机等对共混材料的亲水性能、热性能和力学性能等进行研究与分析。结果表明，亲水处理剂聚乙二醇（PEG）、聚丙烯酸钠（PAAS）、聚乙烯吡咯烷酮（PVP）均能改善PET的亲水性能，影响PET的结晶性能，但亲水处理剂对PET的力学性能影响较小，其中PET/PEG共混材料的亲水性最优；随着PEG含量的增加，PET/PEG共混材料的亲水性先逐渐增强，当PEG含量高于5 %后，共混材料的亲水性变化很小；且PET的结晶度随着PEG的加入呈现先增大后减小的趋势。     

High‐performance thermosets with tailored properties derived from methacrylated eugenol and epoxy‐based vinyl ester

A renewable chemical, eugenol, is methacrylated to produce methacrylated eugenol (ME) employing the Steglich esterification reaction without any solvent. The resulting ME is used as a low‐viscosity co‐monomer to replace styrene in a commercial epoxy‐based vinyl ester resin (VE). The volatility and viscosity of ME and styrene are compared. The effect of ME loading and temperature on the viscosity of the VE–ME resin is investigated. Moreover, the thermomechanical properties, curing extent and thermal stability of the fully cured VE–ME thermosets are systematically examined. The results indicate that ME is a monomer with low volatility and low viscosity, and therefore the incorporation of ME monomer in VE resins allows significant reduction of viscosity. Moreover, the viscosity of the VE–ME resin can be tailored by adjusting the ME loadings and processing temperature to meet commercial liquid molding technology requirements. The glass transition temperatures of VE–ME thermosets range from 139 to 199 °C. In addition, more than 95% of the monomer is incorporated and fixed in the crosslinked network structure of VE–ME thermosets. Overall, the developed ME monomer exhibits promising potential for replacing styrene as an effective low‐viscosity co‐monomer. The VE–ME resins show great advantages for use in polymer matrices for high‐performance fiber‐reinforced composites. This work is of great significance to the vinyl ester industry by providing detailed experimental support. © 2018 Society of Chemical Industry     

严寒地区单体建筑太阳能-相变墙系统蓄热特性研究

利用太阳能对水加热并通入相变墙进行蓄热，对减少严寒地区单体建筑供热能耗有重要意义。以大庆市某单体建筑为例，结合该地区太阳能分布特点及建筑热负荷大小，对适用于该地区的太阳能-相变墙系统进行集热与储热能力计算，并采用CFD方法研究单一工况下该系统的热工变化规律及不同热水参数、换热管规格对相变墙蓄热特性的影响。结果表明：该相变墙热稳定性良好，但受自然对流影响，底部相变材料熔化较慢；管径DN25、入口流速0.3m/s、供水温度310.15K、回水温度309.15K、管间距107mm可使相变材料在4小时内完成蓄热，平均节能率为31.8%。研究结果可望为降低严寒地区建筑供热能耗提供新思路。     

Amine-containing olefin copolymer with CO2-switchable oil absorption and desorption

Global decrease in crude oil resources and frequent crude oil leaks cause the energy crisis and ecological pollution. The absorption and release of leaked crude oil through absorption materials are a necessary process for environmental protection and recycling. In this article, a CO₂-responsive olefin copolymer was obtained by copolymerization of styrene and an amine-containing olefin monomer. The structure of resultant copolymer was characterized by FTIR; thermal properties and CO₂-responsive morphology changes were determined by DSC/TGA and SEM, respectively. Copolymers had certain absorption capacity for toluene with absorption rate up to 180.0%. The absorbed toluene could be released upon CO₂ stimulation with desorption rate up to 84.6%. The CO₂-responsive copolymer could be regenerated through a simple heating process and showed stable absorption–desorption performance even after being recycled for 4 times. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47439.     

Preparation and polymerization of isopimaric acid derivatives

Isopimaric acid is a typical rosin compound and can account for 30% of the total mass of slash pine rosin. The molecular structure of isopimaric acid derivatives features an unsaturated double bond at the C13 position, opening up the possibility of their industrial polymerization. In this study, isopimaric acid (95.4%), methyl isopimarate (99.5%), and allyl isopimarate (95.1%) were prepared as highly pure monomers. New experimental results are presented and mechanisms based on the investigation of free-radical polymerization under UV irradiation are proposed. New rosin monomers for potential value-added utilization of woody biomass are also identified. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47817.