红外光谱法测定干酪素与丙烯腈接枝共聚物的组成

以干酪素vc-o的特征吸收峰(1244cm^-1)和丙烯腈vcmN的特征吸收峰(2244cm^-1)为测定波长,利用二者的吸光度比值与干酪素和丙烯腈接枝共聚物中丙烯腈的百分含量呈线性的关系,建立了利用红外光谱测定干酪素与丙烯腈接枝共聚物组成的方法,线性范围为22％～54％,相关系数r=0．9911,相对标准偏差(RSD)为1．50％。该法简便、快速,有良好的稳定性。     

Fe(acac)3-Al(i-Bu)3-α,α''-联吡啶催化丙烯腈与苯乙烯共聚合

研究了Fe(acac)3-Al(I-Bu)3-α,α'-联吡啶(acac=乙酰丙酮)催化体系催化丙烯腈(AN)与苯乙烯共聚合, 用元素分析和核磁共振研究了共聚物的结构, 在单体比为1:1时共聚物中丙烯腈/苯乙烯含量分别为49.3%和50.7%. 用凝胶渗透色谱研究了聚合物分子量和分子量分布, 共聚物分子量分布较窄. 动力学研究表明共聚合反应对单体浓度呈一级关系,表观活化能为57.8 kJ/mol.     

Fe(acac)_3-Al(i-Bu)_3-α,α′-联吡啶催化丙烯腈与苯乙烯共聚合

研究了Fe(acac)3-A l(i-Bu)3-α,α′-联吡啶(acac=乙酰丙酮)催化体系催化丙烯腈(AN)与苯乙烯共聚合,用元素分析和核磁共振研究了共聚物的结构,在单体比为1∶1时共聚物中丙烯腈/苯乙烯含量分别为49.3%和50.7%.用凝胶渗透色谱研究了聚合物分子量和分子量分布,共聚物分子量分布较窄.动力学研究表明共聚合反应对单体浓度呈一级关系,表观活化能为57.8 kJ/mol.     

SBS辐射接枝α-甲基丙烯酸(MAA)及含量的测定

采用辐射接枝共聚法制备了苯乙烯-丁二烯-苯乙烯嵌段聚合物（SBS）接枝α-甲基丙烯酸（MAA）的接枝聚合物（SBS-g-MAA）.研究了辐射接枝反应中单体转化率、接枝率的变化规律.结果表明：当单体浓度为0.10g/mL时,接枝率可达到10.9%;辐照前滤去多余含有单体的清液,会使接枝率下降,可同时减少单体的均聚,由于滤出的液体可重复使用,提高了单体的利用率,从而降低成本.用滴定法和红外分光光度法结合,建立了以SBS-g-MAA中1 705cm^-1羰基峰的峰面积与SBS的1 493cm^-1苯乙烯的特征峰作为内标峰的峰面积之比,与滴定分析测定的接枝量,通过线性拟合得到了红外定量分析工作曲线与公式,二者具有良好的相关性,该表达式可用于快捷表征SBS-g-MAA中MAA的含量.     

Fe（acac）3-Al（i-Bu）3-α，α＇-联吡啶催化丙烯腈与苯乙烯共聚合

研究了Fe（acac）3-Al（i-Bu）3-α，α＇-联吡啶（acac=乙酰丙酮）催化体系催化丙烯腈（AN）与苯乙烯共聚合，用元素分析和核磁共振研究了共聚物的结构，在单体比为1：1时共聚物中丙烯腈／苯乙烯含量分别为49．3％和50．7％．用凝胶渗透色谱研究了聚合物分子量和分子量分布，共聚物分子量分布较窄．动力学研究表明共聚合反应对单体浓度呈一级关系，表观活化能为57．8kJ／mol．     

较高等规度丙烯腈成纤聚合物的合成

以无水氯化镁为添加剂,考察了不同条件下的丙烯腈聚合反应,研究了溶剂种类、聚合温度和氯化镁与丙烯腈的摩尔配比对聚合反应及聚合物等规度的影响,并确定了最佳反应条件,正己烷为溶剂,偶氮二异丁腈(AIBN)为引发剂,聚合温度为60℃,氯化镁与丙烯腈的摩尔比为2∶1.在此条件下,研究了单体浓度和引发剂浓度对丙烯腈(AN)均聚合、丙烯腈/衣康酸(AN/IA)二元共聚合和丙烯腈/衣康酸/丙烯酸甲酯(AN/IA/MA)三元共聚合反应的影响,并获得了较高等规度(三单元组全同分数30.2%～55.9%)的丙烯腈均聚物和共聚物.不同等规度的丙烯腈聚合物的热分析(DSC及TGA)表明,随着聚合物等规度的提高,聚合物的环化放热峰值温度向高温区移动,而且随着聚合物等规度的提高,环化放热峰变宽.随着聚合物等规度的提高,聚合物的热稳定性变差,热失重增加,碳收率降低.     

GC–MS法测定ABS,SAN中残留苯乙烯和丙烯腈单体

建立了气相色谱–质谱法同时测定ABS(丙烯腈–丁二烯–苯乙烯)及SAN(苯乙烯–丙烯腈共聚物)塑料中2种残留单体丙烯腈和苯乙烯的方法。用N,N-二甲基甲酰胺(DMF)萃取,用甲醇将高聚物进行沉淀,分离后取上清液进样分析。丙烯腈及苯乙烯的线性范围为1~500 mg/L,相关系数分别为0.959 7和0.992 9。加标回收率为82.3%~102.2%,测定结果的相对标准偏差为0.74%~2.67%(n=6),检出限(S/N=3)为1.0 mg/kg。该方法灵敏度、准确度高,适合于ABS和SAN中丙烯腈和苯乙烯的检测。     

极性单体对苯乙烯—二乙烯苯共聚反应的影响及动力学研究.Ⅰ.

本文对分别加入丙烯腈、醋酸乙烯酯和甲基丙烯酸甲脂的苯乙烯—二乙烯苯共聚反应体系进行了动力学研究,并考察了聚合物的溶胀性能以及所合成的离子交换树脂的交换量和强度。结果表明:在苯乙烯—二乙烯苯共聚反应体系中,加入少量的极性单体,改变了苯乙烯与二乙烯苯的相对聚合速率,从而起到了调节共聚物中化学交联点分布的作用。共聚物网络结构的这一变化使其溶胀性能和强度也相应地发生了一定变化。     

尿素作为造孔剂对聚乙烯支撑的PAMS聚合物电解质性能的改进

采用乳液聚合法合成聚(丙烯腈-甲基丙烯酸甲酯-苯乙烯) (P(AN-MMA-ST)或者共聚物PAMS), 并利用尿素作为造孔剂制备了聚乙烯(PE)支撑的PAMS聚合物膜(PE-PAMS-U)及凝胶聚合物电解质(GPE). 利用傅里叶变换红外(FTIR)光谱、X射线衍射(XRD)、扫描电子显微镜(SEM)、热重(TG)分析、线性电位扫描(LSV)、电化学阻抗谱(EIS)以及充放电等方法对PAMS聚合物以及PE支撑的聚(丙烯腈-甲基丙烯酸甲酯-苯乙烯) (PE-PAMS)聚合物隔膜及凝胶聚合物电解质的性能进行了研究. 结果表明, 利用尿素作为造孔剂可以提高PE-PAMS凝胶聚合物的性能. 由于尿素的加入, 聚合物膜呈现均匀的微孔结构, 室温下的电导率从1.1×10^-3 S·cm^-1提高到2.15×10^-3 S·cm^-1. 同时, 锂电极/聚合物电解质界面上的电荷传递电阻也从480 Ω·cm²降低到 250 Ω·cm². 电化学稳定窗口为5.0 V. 电池(Li/PE支撑的GPE/LiCoO₂)的测试证明, 用尿素作为造孔剂的凝胶聚合物锂离子电池表现出优良的倍率性能和循环性能.     

热塑性聚合物红外定性分析快速制样方法的研究

研究了热塑性聚合物红外光谱定性分析制样方法。提出了一种高效、简单、准确的熔融拉膜的制样方法,适用于聚乙烯、聚丙烯、聚苯乙烯、丙烯腈－丁二烯－苯乙烯（ＡＢＳ）、乙烯－醋酸乙烯酯（ＥＶＡ）、聚碳酸酯、聚甲基丙烯酸甲酯、聚甲醛。     

聚碳酸酯与苯乙烯-丙烯腈共聚物共混体系相容性及其对光学性能的影响

利用分子内链段排斥性相互作用理论研究了聚碳酸酯 (PC) 苯乙烯 丙烯腈共聚物 (SAN)共混体系中组份分子量及SAN共聚比例对体系相容性的影响规律 ,确定了获得均相的PC SAN共混体系的条件 ,考察了体系相容性与光学性能之间的关系 .通过实验获得了均相的PC SAN共混物 ;研究结果表明PC聚合度为 90、SAN聚合度为 3 0的PC SAN(S体积含量为 68%)体系共混比在 60∶40附近时体系的双折射能够实现补偿 ,紫外透光率达到 70 %.     

Synthesis and polymerization of 2-butyl-7-methylene-1,4,6-trioxaspiro(4,4)nonane

2-Butyl-7-methylene-1,4,6-trioxaspiro(4,4)nonane ( 7 ) was prepared by the reaction of 2-(bromomethyl)-5-oxo-tetrahydrofuran with 1,2-epoxyhexane, followed by dehydrobromination. Compound 7 could be polymerized by free radical initiators to give a viscous polymer. The IR and NMR spectra of the polymers indicated that the polymer structure contained ester and ketone units in the backbone, and a cyclic acetal side chain. Compound 7 readily copolymerized with acrylonitrile in the presence and absence of radical initiators, but did not copolymerize well with styrene. Ultraviolet spectra suggest that the spontaneous polymerization proceeds via a chargetransfer complex between 7 as an electron donor and AN as an electron acceptor.     

Homopolymers and copolymers of acrylates and methacrylates of homoterpenylmethyl carbinol and α-campholenol

Acrylates and methacrylates of homoterpenylmethyl carbinol and α-campholenol were homopolymerized. Copolymers with each other and acrylonitrile were studied. Terpolymers of the acrylate of homoterpenylmethyl carbinol and the acrylate of α-campholenol with butadiene and styrene or acrylonitrile were also prepared. The lactone ring in the homopolymer of methacrylate of homoterpenylmethyl carbinol was opened up under basic conditions at room temperature, yielding a water-soluble polymer. Films of this polymer were cast from a water solution. The acrylate of homoterpenylmethyl carbinol gave a high molecular weight copolymer with acrylonitrile which could be molded into a transparent, extremely tough, film. The terpolymers of the acrylate of homoterpenylmethyl carbinol with butadiene and styrene or acrylonitrile were obtained in high yield and could be molded into strong, rubbery films. Several polymers were epoxidized and cured with p-phenylenediamine.     

Polymeric formamides as liquid–liquid phase transfer catalysts

Polymeric formamides were prepared by free radical polymerization of N-methyl-N-vinyl-formamide or N-methyl-N-(4-vinylbenzyl)formamide, and copolymerization of these monomers with styrene. These soluble polymers serve as phase transfer catalysts for several reactions under liquid–liquid biphase conditions. The catalytic activity of copolymers containing styrene unit is affected remarkably by composition, and there are maxima at certain composition in both polymers. However, copolymers with an acrylonitrile co-unit scarcely exhibit catalytic activity. Furthermore, it was found that these polymers can extract all alkali metal ions employed here, and that the extraction ability increases with increasing the density of active sites. From these results, it is demonstrated that catalytic activity strongly depends on both cation extraction ability of polymers and lipophilicity around the active sites in the polymer.     

Monomer reactivity ratios in graft copolymerization

This paper discusses monomer reactivity ratios in various radiation- and redox-initiated graft copolymerizations. The polymers studied were polyethylene, cellulose acetate, poly(vinyl chloride), polytetrafluoroethylene, poly(vinyl alcohol), and poly(methyl methacrylate); the comonomer mixtures were styrene–acrylonitrile, methyl acrylate–styrene, acrylonitrile–methyl acrylate, and vinyl acetate–acrylonitrile. The polymer–comonomer mixture systems were so chosen as to permit study of both homogeneous and heterogeneous systems. The homogeneous systems included systems of low and high viscosity. The heterogeneous systems included both polymers swollen by the comonomer mixture and polymers not swollen by the comonomer mixture. None of the homogeneous grafting systems studied showed deviations from the normal copolymerization behavior under a variety of experimental conditions. Monomer reactivity ratios in graft copolymerization were the same as the values in nongraft copolymerization. The heterogeneous systems in which the polymer was swollen by the comonomer mixture yielded grafted copolymer compositions which were the same as those in nongraft copolymerization. The heterogeneous grafting system polytetrafluoroethylene/styrene–acrylonitrile showed deviations from normal copolymerization behavior at low degrees of grafting when the reaction was only on the polymer surface. The behavior became normal at higher degrees of grafting when the system approaches that in which the polymer is swollen by the comonomers. In all reaction systems, it was found that the use of radiation to initiate the reaction does not in any way affect the copolymerization behavior of the two monomers in a comonomer pair.     

Polarons radical polymerization

Polystyrene has been typically prepared with radical polymerization by benzoyl peroxide (BPO) or azobisisobutyronitrile (AIBN). In this report, polymerization of styrene was carried out by radical cations of polyaniline (PANI). Polarons of conducting polymers are consisting of radical cations. The polarons bear electrical conduction as a charge carrier. We employ the polarons as an initiator for radical polymerization. Polymerization of styrene and acrylonitrile by the polarons was conducted to explore new possibility of conducting polymers. Fourier‐transfer infrared absorption (FTIR) spectroscopy measurements for the resultant polymers obtained with polarons of polyaniline indicates that the polystyrene thus synthesized grows from polyaniline. The qualitative solubility, average molecular weight, and thermal stability are comparable to that of polystyrene obtained by the common method with BPO. Radical polymerization by polarons may provide a new avenue for radical polymerizations through application of conducting polymer. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 805–811     

Preparation of pinewood/polymer/composites using gamma irradiation

Wood/polymer composites (WPC) have been prepared from pinewood with different compounds using gamma irradiation: butyl acrylate, butyl methacrylate, styrene, acrylamide, acrylonitrile, and unsaturated polyester styrene resin. The polymer loading was determined with respect to the compound concentration and the irradiation dose. The polymer loading increases generally with increase in the monomer or polymer concentration. Tensile and compression strength have been improved in the four cases, but no improvement was observed using unsaturated polyester styrene resin or acrylamide.     

碳纳米管在聚丙烯腈中的分散状态

采用原位聚合法合成了不同碳纳米管(CNT)含量的碳纳米管／聚丙烯腈(CNT／PAN)复合材料,并利用X光电子能谱(XPS)、紫外、红外、扫描电镜等对产物进行了表征。结果表明：在原位聚合反应中,碳纳米管与PAN形成化学键合,大量碳纳米管均匀地分布在基体PAN内部,与PAN形成了良好的界面。     

Emission Profiles of Volatiles during 3D Printing with ABS,ASA, Nylon,and PETG Polymer Filaments

In this short communication we characterize the emission of volatile organic compounds (VOCs) from fused filament fabrication (FFF) 3D printing using four polymer materials, namely polyethylene terephthalate glycol-modified (PETG), acrylonitrile styrene acrylate (ASA), Nylon, and acrylonitrile butadiene styrene (ABS). Detailed emission profiles are obtained during thermal degradation of the polymers as a function of temperature and also in real-time during 3D printing. Direct quantitative measurement was performed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Qualitative determination of the volatiles emitted from the printed elements at various temperatures was accomplished using gas chromatography-mass spectrometry (GC-MS). The emission rates of VOCs differ significantly between the different polymer filaments, with the emission from Nylon and PETG more than an order of magnitude lower than that of ABS.     

Synthesis and properties of cyclopropane-containing optically transparent polymers

New cyclopropane-containing optically transparent polymers were prepared by radical homopolymerization of p-(2-methoxycarbonylcyclopropyl)styrene and by its binary copolymerization with styrene and methyl methacrylate. The composition and structure of these macromolecular compounds were determined, and their main service characteristics were evaluated.