N-苯基马来酰亚胺改性MCS接枝共聚物的合成与热性能研究

用N-苯基马来酰亚胺（N-PMI）作耐热改性剂，通过悬浮聚合法合成了接枝型MCS树脂，并对其热性能进行了研究。结果表明，N-PMI成功接枝在基体树脂上，接枝改性后的MCS树脂的热性能得到了明显的改善，玻璃化温度和热分解温度明显提高。     

PB-g-SAN共聚物的接枝层厚度对增韧SAN树脂的影响

采用种子乳液聚合方法制备了聚丁二烯接枝丙烯腈苯乙烯共聚物（PB g SAN）,将PB g SAN共聚物与SAN树脂熔融共混获得丙烯腈丁二烯苯乙烯三元共聚物(ABS),研究了PB g SAN共聚物的接枝层厚度对ABS性能的影响。结果表明,接枝层厚度超过临界值117 nm,接枝层过厚会导致核壳改性剂粒子变硬,模量过高,从而失去了作为增韧改性剂的作用。接枝层厚度低于临界值32 nm,橡胶粒子不能被SAN接枝链完全覆盖,在SAN基体中发生聚集,导致其增韧效果降低。因此,只有改性剂的接枝层厚度介于32 nm和117 nm这两个临界值之间,才能对基体树脂起到有效的增韧作用。     

淀粉接枝共聚物的合成与絮凝性能研究

用淀粉与甲基丙烯酸甲酯及苯乙烯单体接枝共聚合成一种新的高分子絮凝剂。共聚物红外光谱表明单体成功接枝到淀粉主链。实验研究了引发剂浓度,淀粉浓度对产物接枝效果的影响。当过氧化氢浓度为0.06 mol/L,淀粉浓度为5%(w/v),产品有较高的接枝率和接枝效率。高岭土悬浊液中的絮凝试验,验证了产品具有优良絮凝性能,并分析相关因素对其絮凝性的影响。     

水性环氧-苯丙接枝共聚物的合成

采用溶液聚合方法,以过氧化苯甲酰(BPO)为引发剂,将苯乙烯、甲基丙烯酸甲酯、甲基丙烯酸接枝到环氧树脂高分子链上后,中和、乳化制得水性环氧-苯丙接枝共聚物。并对水性环氧-苯丙接枝共聚物的亲水性、水分散稳定性和分子结构进行表征,确定了合成环氧-苯丙接枝共聚物的最佳条件:反应温度为115℃,反应时间为6 h,BPO用量为环氧树脂及接枝单体总质量的1.6%,亲水单体甲基丙烯酸用量占环氧树脂及接枝单体总质量的10%,三异丙醇胺用量占成功接技的甲基丙烯酸物质的量的95%。     

辐射接枝SBS的性能研究

采用旋转流变仪研究了苯乙烯-丁二烯-苯乙烯（sgs）嵌段聚合物接枝α-甲基丙烯酸（MAA）、甲基丙烯酸甲酯（MMA）接枝共聚物（SBS-g-MAA，SBS-g-MMA）的动态流变性能。结果表明：接枝共聚物的黏流活化能降低，温度敏感性降低；比较改性前后的共聚物的主曲线，接枝共聚物的相对分子质量分布变宽，在剪切应力作用下，黏度下降较快；接枝共聚物的相对分子质量分布变宽，接枝共聚物的抗氧化性增强。     

木薯淀粉/VAc-MA接枝共聚物的合成研究

通过正交试验设计,研究醋酸乙烯酯和丙烯酸甲酯两种单体接枝改性木薯淀粉的影响因素。利用SAS统计分析得出适宜的工艺条件:引发剂浓度16mmol.L-1,总单体浓度1.45mol.L-1,两单体配比(VAc/MA)为30/70,反应温度65℃,反应时间5h。采用红外光谱对该接枝共聚物结构进行了分析。     

SBS接枝MMA合成的共聚物对PS/PVC共聚物增容作用的研究

结合共聚原理,成功地确定了此接枝共聚物作为PS/PVC共混体系的增容作用。并分析了此接枝共聚物的力学性能。应用接枝或嵌段共聚物作为第3组分加入到二元不相容的高聚物共混体系中被认为是控制相态结构、改善力学性能简单而有效的方法。由此,合成非反应性接枝共聚物作为二元不相容的高聚物共混物的第3组分是研究的主要课题。     

Synthesis and Characterization of Graft-type MCS Resin

Abstract

MCS resin, formed from methyl methacrylate (MMA), styrene (St), chlorinated polyethylene (CPE), was synthesized by suspension swelling graft-copolymerization. In this paper, the synthesis conditions of MCS, the effect of different synthesis conditions on graft efficiency, the mechanical properties, rheological behavior and morphology were investigated. The graft efficiency increased with increasing CPE content. The apparent viscosity of melt increased with increasing the content of CPE. The copolymer composition was analyzed by FTS-40 Fourier transform infrared spectrometer and PE-2400 element analyzer. The fractured surface morphology of MCS resin was observed by SEM and X-ray energy dispersive spectroscopy.     

氯化原位接枝技术制备改性CPVC的研究

采用氯化原位接枝技术制备了改性CPVC,研究了在气固相中氯化接枝的规律,讨论了单体苯乙烯（St）和甲基丙烯酸甲酯（MMA）用量、氯含量以及氯化反应温度对产物性能的影响。结果表明,单体用量为10份左右时,改性CPVC的屈服强度高于CPVC的屈服强度;加入St改性后,氯化反应温度120℃时可得到屈服强度较高的CPVC—g—St;在135℃可得到维卡软化点较高的CPVC—g—St;单体用量适当,可同时提高改性CPVC的屈服强度和韧性。     

氯化聚乙烯接枝马来酸酐胶粘剂的研究

本文介绍了改性聚丙烯（PP）基泡沫材料用的水溶性胶粘剂的研制。该胶粘剂不影响泡沫材料的阻燃性能和吸声性能，并有较好的热稳定性和储存性以及优化的耐水性。     

甲基丙烯酸甲酯-N-环己基马来酰亚胺-苯乙烯三元共聚物的研究

研究了甲基丙烯酸甲酯-N-环己基马来酰亚胺-苯乙烯三元共聚体系中苯乙烯用量对共聚物的透光性、黄色度、耐热性、物理机械性能及加工流动性的影响。结果表明：在不影响产品透光性的前提下，St的加入可明显降低产品的黄色度；适量的St可提高共聚物的耐热性并改善共聚物的力学性能。苯乙烯的用量为甲基丙烯酸甲酯和N-环己基马来酰亚胺总质量的15％时，可以得到综合性能良好的共聚物。     

两亲性接枝物CPE-g-AM-MAH的合成条件研究

采用悬浮溶胀法将丙烯酰胺(AM)、马来酸酐(MAH)与氯化聚乙烯(CPE)进行接枝反应,制备得到了两亲性共聚物(CPE-g-AM-MAH),用红外光谱对接枝物结构进行了表征,利用正交试验法讨论了氯化聚乙烯、马来酸酐、AM/MAH比率、引发剂对接枝率和接枝效率的影响.结果表明:各影响因素对接枝率的影响顺序为AM>CPE>...     

Studies on the graft polymerizations of styrene and methyl methacrylate to hydroxyl terminated polybutadiene

Hydroxyl terminated Polybutadiene (HTPB) was grafted with styrene (St) or methyl methacrylate (MMA) by free radical solution polymerization. The graft copolymerizations were conducted in benzene at 70 °C. The initiators used were benzoyl peroxide (BPO) and azobis-isobutyronitrile (AIBN). The microstructures of theobtained graft copolymers were characterized by¹³C NMR measurement and the DEPT technique, as well as by IR spectrometer. The mechanism of grafting reactions was determined from the microstructures of derived graft copolymers. It showed that graft copolymer resulted when BPO was used as initiator of the vinyl monomer polymerization, but not with AIBN. It appeared that the reaction leading to graft formation was direct attack of oligomeric styrene radicals or double bonds of the HTPB. Whereas the graft copolymerization of MMA to HTPB was the same as that suggested in the literature i.e., by a hydrogen abstract reaction.     

Studies on the curing behaviour and mechanical properties of styrene/methyl methacrylate grafted deproteinized natural rubber latex

The graft copolymerization of styrene/methyl methacrylate (MMA) onto deproteinized natural rubber (DPNR) latex was carried out using ammonium peroxy disulfate (N₂H₈O₈S₂) as the initiator. The presence of the grafted polystyrene (PS) and polymethyl methacrylate (PMMA) on the rubber backbone was confirmed by FTIR spectroscopy. The effects of monomer concentrations on curing characteristics and mechanical properties were studied. It was found that the cure time and scorch time were increased with increasing monomer concentration whereas the torque_max–min value was slightly decreased. It was also noted that the increase in the monomer concentration resulted in stiffer rubber with increased modulus and reduced elongation at break.