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。     

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.     

基于迁移学习的有机硅单体分馏过程能耗建模

有机硅单体分馏过程需分离的物质多且分离技术要求高，是有机硅单体生产过程中能耗较高的单元之一。能耗模型的建立对分馏过程的生产优化有着重要的意义。虽然分馏过程中各提纯单元的塔器设备型号、操作条件存在差异，但由于各提纯单元存在相似性，如何充分利用这些相似性进行能耗建模，从而减少建模过程中对数据量、质的要求是要解决的问题。通过引入迁移学习算法，增大源单元和目标单元数据域的相似性，实现不同数据域的知识传递，充分利用现有数据中包含的知识，建立新的能耗模型。以某有机硅企业采集的现场数据进行算法验证，结果显示，当训练样本量不足时，迁移学习可以有效提升模型性能，从而验证了该算法的有效性与实际应用价值。     

生物基聚酯与聚酰胺纤维的研发进展

为促进我国化纤行业转型升级与持续发展,对以生物基聚对苯二甲酸乙二醇酯纤维、聚对苯二甲酸-1,3-丙二醇酯纤维、聚乳酸纤维、聚呋喃二甲酸乙二醇酯纤维、聚呋喃二甲酸丙二醇酯纤维,以及生物基聚酰胺56纤维为代表的生物基聚酯、聚酰胺纤维的国内外生产现状,市场需求、技术发展及趋势进行了综述,对全球生物基纤维专利的分布、各主要开发机构的专利战略及技术情况进行了梳理及剖析。在此基础上结合国内高分子材料产业实际,对我国生物基聚酯、聚酰胺纤维的发展建言应重点攻关生物基乙二醇、对苯二甲酸、己二胺等战略性生物基单体制备的核心技术,同时就重点任务和发展路径提出了建议。     

Photoinitiated synthesis of poly(poly(ethylene glycol) methacrylate-co-diethyl amino ethyl methacrylate) superabsorbent hydrogels for dye adsorption

Random copolymers of poly(ethylene glycol) methacrylate (PEGM), and diethyl amino ethyl methacrylate (DEAEM) were synthesized at low, and high conversions by photoinitiation. Crosslinked poly(PEGM-co-DEAEM) samples were obtained, and characterized by FTIR, SEM, DSC, TGA, and elemental analyses. Swelling behavior of the copolymers revealed that the copolymers acted as superabsorbent hydrogels. The monomer reactivity ratios were calculated using Fineman Ross, Extended Kelen Tüdøs , and Mayo Lewis methods that gave r₁(PEGM) = 0.90, r₂(DEAEM) = 0.14 at low conversions. At high conversions r₁ and r₂ values were calculated as 1.01 and 0.40, respectively. Adsorption isotherms of methyl orange (MO) onto hydrogels were studied using Langmuir, Freundlich, and Temkin models. The experimental data fitted well with the Langmuir equation. The maximum adsorption capacity for MO was 212.7 mg g⁻¹ at pH = 3. The adsorption data gave best fit with the pseudo-second order kinetic model. Thermodynamic evaluation showed spontaneous nature for MO adsorption onto poly(PEGM-co-DEAEM) hydrogels. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47707.     

三元乙丙橡胶/聚丙烯热塑性硫化胶细观力学数值模拟分析Ⅱ.三元乙丙橡胶结构对细观力学性能的影响

通过建立三元乙丙橡胶(EPDM)/聚丙烯(PP)热塑性硫化胶(TPV)的细观尺寸多颗粒随机分布的RVE模型,研究了分散相EPDM粒子形状及大小、间距对TPV应力和弹性模量的影响。结果表明,在分散相EPDM体积分数不变的条件下,EPDM粒子形状越接近圆形,TPV的应力值越低,EPDM粒径的减小可提高TPV的弹性模量;EPDM粒子间距增大,TPV的应力值下降,TPV中EPDM体积分数越高,其应力值受EPDM粒子间距的影响越显著。     

马来酸单聚乙二醇单甲醚酯的合成及应用

采用无溶剂法合成了马来酸单聚乙二醇单甲醚酯,并对其合成工艺进行了探讨。实验以原料醇酸物质的量比、催化剂用量、阻聚剂用量、反应温度和反应时间为5因素,设计成5因素4水平的正交实验,由实验确定出组分质量分数和最佳酯化反应条件：醇酸物质的量比1.0∶1、催化剂质量分数5%、阻聚剂质量分数3%、反应温度120℃,反应时间为5 h,最佳酯化条件下酯化率达到95.25%。进一步由大单体与丙烯酸、丙烯酸丁酯、烯丙基苯磺酸钠共聚制备出水煤浆分散剂,由大同煤制浆,在分散剂质量分数为1.0%,干粉煤质量分数为65%时,水煤浆粘度为1550mPa·s-1,静置90min后,粘度为2100mPa·s-1。