聚氯乙烯树脂接枝改性加料工艺对性能的影响

本试验以悬浮法聚氯乙烯树脂为接枝母体，以挤冲改性剂ＭＢＳ的三种单体为接枝单体，采用悬浮聚合主地一些聚合条件进行了探索，取得了一些进展，为开拓聚氯乙烯树脂中化学改性这个新的研究领域作出了贡献。     

硬聚氯乙烯制品的增韧改性研究

采用偶联剂对活性ＣａＣＯ３进行表面活化处理，与弹性粒子ＣＰＥ混杂填充硬质ＰＶＣ。以改善由于ＣＰＥ和ＰＶＣ共混造成的硬质ＰＶＣ体系某些性能下降的缺陷。ＰＶＣ／ＣＰＥ／ＣａＣＯ３＝１００／１０／１５的混合体系，冲击强度达２３．７ｋＪ／ｍ２，拉伸强度４８．４ＭＰａ、弯曲强度：７４．５ＭＰａ，熔融时间３．４ｍｉｎ、最大扭矩４４．２Ｎ·ｍ，维卡软化点９４．２℃。     

聚氯乙烯树脂耐热和增韧改性研究进展

综述了聚氯乙烯（PVC）树脂耐热改性和增韧改性的研究进展。PVC耐热改性方法主要有添加热稳定剂、交联、共混、共聚、氯化及无机纳米粒子改性;增韧改性的主要方法包括弹性体、纳米粒子、聚合物/无机纳米复合材料、纳米级微纤增韧以及原位聚合的方法。最后,提出了PVC耐热和增韧改性的发展方向。     

聚氯乙烯增韧改性研究进展

介绍了目前国内外PVC增韧改性的研究现状、增韧改性剂的种类和增韧机理以及PVC增韧研究的发展方向。     

氯化聚氯乙烯改性材料研究进展

文中总结了近２０年有关氯化聚氯乙烯共混材料,填充及复合材料接枝共聚材料方面的研究及开发应用进展,重点介绍了材料的发展现状。     

聚氯乙烯增韧改性研究新进展

综述了聚氯乙烯增韧改性的2种改性方法即物理共混改性法和化学交联改性法的研究进展,并介绍了聚氯乙烯增韧改性的机制。     

纤维素接枝共聚改性的若干途径

纤维素接枝共聚是对纤维素进行改性的重要方法之一。本文综述了迄今用于纤维素接枝共聚改性的若干主要途径，其中包括自由基型接枝共聚，离子型接枝共聚以及缩聚型接枝共聚三大类。     

聚氯乙烯低温增韧改性研究进展

本文对近年国内外关于聚氯乙烯塑料低温增韧改性研究中具有代表性的方法进行了总结。分别介绍了弹性体改性、无机纳米粒子改性、复合增韧改性的机理,并对其发展前景进行了展望。     

氯乙烯—聚丙烯酸酯接枝共聚树脂特性研究

研究了氯乙烯—聚丙烯酸酯接枝共聚树脂的特性。结果表明含6％聚丙烯酸酯(ACR)的接枝共聚物具有好的表观物性、流变行为和易加工性,且显著提高了制品耐候性和力学指标,抗冲击强度是纯PVC的8～9倍,较ACR/PVC共混改性树脂抗冲强度高3倍,在以塑代木应用上具有较高实用价值和效益。     

我国硬质聚氯乙烯增韧改性的进展

介绍了国内增韧聚氯乙烯的材料种类，特点，增韧机理，效果及研究现状。     

Graft copolymerization of methyl methacrylate onto biomedical polyvinyl chloride initiated by Ce(IV)–glucose redox system

Graft copolymerization of methyl methacrylate onto PVC was carried out using Ce(IV)–glucose redox system in aqueous sulfuric acid medium under nitrogen atmosphere. To find out the optimum conditions for grafting, effects of concentrations of metal ion, glucose, monomer, and acid on the percentage of grafting was studied. The graft yield was found to be influenced by reaction time, temperature, and amount of PVC. An appreciably high graft yield could be achieved with the present system. On the basis of the results from the present study, a plausible reaction mechanism has been proposed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2105–2111, 2005     

接枝共聚改性氯化聚丙烯乳液的研究

以丙烯酸酯单体作为接枝共聚单体,合成了无芳烃低VOC的CPP(氯化聚丙烯)乳液。以接枝率和耐水性作为衡量指标,采用单因素试验法优选出制备CPP乳液的最佳工艺条件。结果表明:当反应温度为95℃、反应时间为3.5 h、w(总引发剂)=1.0%(其中10%引发剂在滴加单体以前加入,并且间隔时间为10 min)、w(丙烯酸酯单体)=30%和w(丙烯酸)=5%时,相应CPP乳液的综合性能相对较好,并且其对聚丙烯(PP)基材的附着力相对最好。     

Polymer-based metal adsorbents via graft copolymerization of polyvinyl alcohol with diaminomaleonitrile: A green chemistry approach

Synthesis, characterization, and amidoximation of diaminomaleonitrile-functionalized polyvinyl alcohol (PVA) grafts were studied. Ceric ammonium nitrate (CAN) was used as an initiator in an aqueous nitric acid medium under N₂ atmosphere. Optimum conditions for grafting were as follows: monomer concentration [DAMN] = 1.4M, [CAN] = 16 × 10⁻² mol/L, T = 50°C, and t = 2 h. Water uptake of the PVA graft films increased with the increase of grafting yield. The imparted cyano group of the grafted PVA polymer chains (with degree of grafting up to 136%) was converted into amidoxime group by the reaction with hydroxylamine hydrochloride. The grafted polymers were characterized by FTIR spectroscopy, differential scanning calorimetry, and thermal gravimetric analysis. The grafted PVA films are more thermally stable than the ungrafted PVA membrane, because the grafted membrane showed a single degradation pattern despite having two components. A decrease in T_g values is observed as the grafting yield of copolymers increases indicating the incorporation of polydiaminomaleonitrile chains in amorphous copolymers with higher thermal stability. The prepared amidoximated DAMN136-g-PVA was investigated for its properties in removing heavy toxic metals, such as Pb²⁺, Cd²⁺, Zn²⁺, Fe³⁺, Cu²⁺, Ni²⁺, and Co²⁺ from water. The amidoximated film is characterized by a considerably greater binding ability with respect to heavy metals. The nature of the metal ion also has great importance in the amount binding to the polymeric material. The kinetics of the sorption/desorption process for Co²⁺, Ni²⁺, and Zn²⁺ were investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

溶液接枝法合成EPDM-g-SAN

以过氧化二苯甲酰(BPO)为引发剂，正庚烷／环己酮为溶剂，用溶液接枝法合成了高胶含量的苯乙烯(St)-三元乙丙橡胶(EPDM)-丙烯腈(AN)接枝共聚物(EPDM-g-SAN)。研究了反应温度、引发剂浓度、EPDM含量、混合溶剂的配比以及反应时间对接枝共聚合反应的影响。FTIR分析证实EPDM已接枝上SAN支链。实验证明，接枝共聚物对SAN树脂具有良好的增韧效果。     

有机硅接枝共聚改性环氧树脂

有机硅改性环氧树脂可提高环氧树脂的韧性和耐热性,该领域是近年来的研究热点。综述了在不消耗环氧基的前提下,通过接枝共聚引入有机硅链段改性环氧树脂的途径,介绍了改性树脂的微观形态及该领域新近研究进展。     

Enhancing water resistance of paper by graft copolymerization reaction

The chemical graft copolymerization reactions were used to enhance water resistance of paper by reaction of acrylonitrile (AN) monomer onto cellulosic paper sheet in the presence of comonomer (styrene or acrylic acid or itaconic acid) 1 : 1 molar ratio in dimethyl formamide using benzoyl peroxide as free radical initiator under nitrogen atmosphere at 70°C. The infrared spectroscopy confirms that graft copolymerization reaction occurs onto the paper samples. Water absorption test was carried out following the Normal Protocol 7/81 (water absorption by complete immersion) to evaluate the protective effect of the graft treatment onto the paper sheet. It was found that the three graft copolymerization systems reduced the water absorption of the investigated paper and the reduction of water absorption is directly proportional to the grafting %. The wettability of the grafted and ungrafted paper sheet samples were investigated using the wicking time method which exhibits the decreasing of paper sheet wettability using the AN/S comonomers in the graft copolymerization reaction. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

羧甲基甲壳素与丙烯酰胺接枝聚合反应研究

制备了羧甲基甲壳素接枝丙烯酰胺共聚物,讨论了反映温度、时间、引发剂用量、溶剂用量、单体用量对接枝反应的影响。最佳反应条件为：羧甲基甲壳素0．4g,溶济水50mL,引发剂60mg,单体1．6g,反应温度50℃,反应时间3．0h。     

Modification of polypropylene fiber by radiation-induced graft copolymerization of acrylonitrile monomer

Modification of polypropylene fiber was carried out by graft copolymerization of acrylonitrile monomer using the preirradiation method. The influence of synthesis conditions (preirradiation dose, monomer concentration, temperature, draw ratio, and storage) on the degree of grafting was investigated. For all preirradiation doses, the degree of grafting was found to increase with the reaction time. The higher the preirradiation dose, the higher the degree of grafting was. The dilution of monomer with DMF showed peak maxima for the degree of grafting at 80% monomer concentration. Both the initial rate of grafting and the final degree of grafting were found to increase with an increase in the reaction temperature. An activation energy of 31.2 kJ/mol was found for the grafting reaction. The degree of grafting in the drawn fiber showed different behavior as compared to the undrawn fiber. The storage of the irradiated fiber at −4°C prior to the grafting showed a decrease in the degree of grafting initially for a period of 8 days, beyond which the degree of grafting remained constant. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1343–1348, 1998     

Surface modification of polyvinyl chloride with biodegradable monomers

Graft copolymerization of sucrose acrylate (SA) onto 55 μm films of poly(vinyl chloride) (PVC) was investigated with benzophenone or 2,2′-azoisobutironitrile as the initiator. The grafting reactions were carried out in a closed cell containing the films to be treated with a solution of the sensitizer and the monomer. In this system, ultraviolet light through a quartz window initiated the reaction by exciting the initiator used. The grafting took place on a PVC surface layer, from the solution. The homopolymer formed during copolymerization was removed by washing. The percentage of grafting was determined by gravimetric measurements and by dye adsorption (crystal violet), and the characterization of PVC(g)SA was carried out by the use of infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis. The weathering behavior of PVC(g)SA was studied with microorganisms in a growing medium, and the degradation was monitored by the weight loss of the films, FTIR, and SEM. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1195–1201, 1997     

玉米淀粉/丙烯酰胺接枝型高吸水性树脂的合成

本文以硝酸铈铵为引发剂 ,研究了单体浓度、引发剂浓度、反应温度和反应时间等因素对玉米淀粉与丙烯酰胺接枝共聚制备高吸水性树脂的影响 ,通过反应条件和正交试验 ,确定了最适宜的反应条件和工艺路线 ,制备出了吸水率在 4 5 0～ 70 0g·g-1的玉米淀粉接枝型高吸水性树脂。