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α-甲基苯乙烯和苯乙烯共聚物乳液的合成及性能研究   总被引:1,自引:0,他引:1  
在不通N2的条件下,采用半连续法,在85℃、乳化剂用量为总量的7.53%时合成出了不同单体配比的α-甲基苯乙烯-苯乙烯共聚物[P(AMS-St)]乳液,其中AMS单体含量最高可达70%以上。用红外、核磁对共聚物结构进行了表征,讨论了加料方式、反应温度、乳化剂用量、单体配比对乳液转化率及稳定性的影响和单体组成与乳液流变性、乳胶粒径大小之间的关系。结果表明随单体中AMS含量的增加,乳液黏度逐渐变大,乳胶粒径逐渐变小,乳胶粒具有均一的尺寸。  相似文献   

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研究了单体组合、分步聚合及加料顺序对乳液聚合法合成发泡调节剂聚合工艺和流变性的影响,确定了按MMA-St、MMA-Mz和St-AN的三种单体组合和三步聚合工艺。  相似文献   

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丁二烯和苯乙烯共聚物橡胶在塑料增韧方面的应用   总被引:1,自引:0,他引:1  
蔡玉壁 《弹性体》2003,13(5):50-52
介绍了丁二烯和苯乙烯共聚物橡胶在塑料增韧方面的应用,同时对国内的有关生产及研究工作提出了一些建议。  相似文献   

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介绍了氯乙烯-丙烯腈共聚物的乳液聚合方法,研究了合成过程中乳化剂、引发剂的加入方式及工艺条件对共聚物性能的影响,并对共聚物进行了表征。结果表明:乳化剂的最佳投加方式为(以乳化剂/VCM表示):先投加0.02,反应开始后流加0.02;引发剂的最佳投加方式为(以引发剂/VCM表示):先投加0.012,反应开始后流加0.012。该共聚物具有优良的阻燃性能。  相似文献   

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以α-溴代异丁酸叔丁酯(t-BBiB)为引发剂,CuBr/2,2′-联二吡啶(Bpy)为催化体系,在70℃下经原子转移自由基聚合(ATRP)反应进行苯乙烯(St)和丙烯腈(AN)共聚合合成苯乙烯/丙烯腈共聚物。采用GC、~1H NMR和GPC对聚合反应过程和聚合产物进行了分析和表征。结果表明:单体浓度的半对数曲线与聚合时间呈线性关系,聚合物摩尔质量随单体转化率的上升而线性增加,而且摩尔质量分布在1.2~1.3之间,表现出活性聚合反应特征。随着聚合反应的进行,共聚物组成趋向于原始单体组成,大分子链存在梯度结构。  相似文献   

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用溶液聚合法合成了丙烯腈-三元乙丙橡胶-苯乙烯接枝共聚物(AES),研究了接枝聚合反应的影响因素,并进行了红外光谱表征。结果表明,三元乙丙橡胶(EPDM)已接枝上丙烯腈(AN)和苯乙烯(St)的共聚物(SAN)支链,即EPDM与AN及St发生了接枝共聚合反应。  相似文献   

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刘艺苑 《塑料加工》1996,24(3):12-14
本文介绍了ASA三元共聚物[丙烯酸酯-苯乙烯-丙烯腈]的结构、耐候性和耐热老化性。概述了ASA树脂在汽车工业、电子电器工业等领域的应用。  相似文献   

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CPP/AN/S接枝共聚物合成及粘接性能研究   总被引:1,自引:0,他引:1  
用丙烯腈 (AN)、苯乙烯 (S)对氯化聚丙烯 (CPP)进行接枝共聚 ,考察了不同条件下制得的CPP/AN/S接枝共聚物胶粘剂对聚烯烃材料的粘接性能 ,结果表明CPP/AN/S共聚物胶粘剂对聚烯烃材料具有较好的粘接性能。  相似文献   

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Terpolymers of N‐phenylmaleimide (PMI), styrene, and acrylonitrile (AN) were synthesized by emulsion polymerization. The thermal properties of terpolymers at different PMI and AN feed contents were investigated by differential scanning calorimetry, torsional braid analysis, thermogravimetric analysis, and a Vicat softening point test. The results showed the glass‐transition temperature and decomposition temperature of the terpolymers increased with increasing PMI feed content. Furthermore, the Vicat softening point of the terpolymers rose with PMI feed content. The weight‐ and number‐average molecular weights (M̄w and n) of the terpolymers were also determined by gel permeation chromatography. The results showed that the w and n of the terpolymers decreased with increasing PMI feed content and increased with increasing AN feed content. The mechanical properties (tensile strength and impact strength) of the terpolymers decreased with increasing PMI feed content and increased with increasing AN feed content. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1067–1073, 2001  相似文献   

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以过硫酸钾为引发剂,十二烷基硫酸钠为乳化剂,叔十二烷基硫醇为链转移剂,通过乳液法对溴化苯乙烯、苯乙烯、丙烯腈进行共聚得到溴化苯乙烯-丙烯腈共聚物.考察了引发剂、乳化剂、链转移剂的添加量,反应温度,反应时间,水和单体比例等对聚合反应收率的影响.研究表明:较适宜的反应条件为反应温度80℃,反应时间6h,水与单体质量比4∶1,引发剂质量为单体总质量的0.4%,乳化剂质量为单体总质量的4%,叔十二烷基硫醇为单体总物质的量的2%;上述条件下的产物收率高,相对分子质量4万左右,热分解温度高于350℃.  相似文献   

13.
环氧改性苯丙乳液的合成及性能   总被引:7,自引:0,他引:7  
采用乳液聚合法制备环氧树脂改性苯乙烯一丙烯酸酯乳液。研究了乳化剂的选择与用量、聚合温度、环氧树脂的用量和功能单体的用量等对改性苯丙乳液综合性能的影响,得到环氧树脂以及甲基丙烯酸的最佳添加量。性能测试表明合成的环氧树脂改性苯丙乳液具有较好的成膜性能和优异的物理机械性能。  相似文献   

14.
为开发性能优良、价格低廉的苯乙烯-丙烯酸酯共聚乳液型水泥外加剂,着重讨论了以丙烯酸酯类和苯乙烯为主要原料、采用预乳化和半连续工艺合成水泥改性型苯乙烯-丙烯酸酯共聚乳液的方法,研究确定了丙烯酸酯类共聚乳液合成的配方设计及单体、乳化剂、引发剂、链转移剂等组分对制备所得的共聚物乳液结果的影响.在丙烯酸用量为单体总量的4%,阴、非离子乳化剂复配使用,乳化剂的量占单体总量的2.5%左右,引发剂用量为单体总量的0.5%时制备的苯丙乳液具有优良的稳定性和机械性能.  相似文献   

15.
In this article, we report on the effect of using ultrasound during emulsion polymerization. This work differs somewhat from that previously reported in that ultrasound is used in conjunction with conventional initiators. The aim is to observe the changes in the nature of polymerization and the synthesized polymer. In this work, reaction conditions and compositions typical of conventional emulsion polymerization are used. Azo‐bisisobutyronitrile and potassium per sulfate are the initiators used. The initial indication is that the rate of polymerization and the final conversion are higher when ultrasound is introduced into the polymerization system. This effect is more pronounced at lower temperatures (50°C) and low initiator concentrations (0.01%). At higher temperatures (70°C) the polymerization rate is seemingly unaffected by the use of ultrasound. The final product in all the experiments is a latex. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 101–104, 2000  相似文献   

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通过熔融共混技术将丙烯腈苯乙烯丙烯酸酯三元共聚物(ASA)对聚对苯二甲酸丁二醇酯(PBT)进行了增韧改性,并采用扫描电子显微镜、动态流变分析仪观察研究了PBT/ASA共混体系的相形态和流变行为。结果表明,ASA可有效增加PBT共混体系的熔体强度,所形成的PBT/ASA共混物为部分相容体系;体系的相容性具有一定的组分依赖性,当ASA含量较低时,共混体系为典型的“海岛”结构,而当ASA含量为40 %~60 %(质量分数,下同)时体系发生了相翻转,该结果与4个预测相翻转的模型中HoRM模型计算得到的相翻转点ASA含量为62.2 %接近。  相似文献   

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Radiation polymerization of acrylonitrile in a viscous system with styrene was performed at ambient temperature by using γ‐rays. It is found that the overall rate of polymerization was accelerated after critical conversion due to the gel effect. As the molar fraction of styrene in monomer feed (fSt) is increased, both the total polymer conversion and molar fraction of acrylonitrile in the copolymer feed (FAN) were decreased. The monomer reactivity ratios for acrylonitrile and styerne were determined to be r1 (AN) = 0.25 and r2 (St) = 2.0, respectively. The copolymers obtained were characterized by Fourier transformed infrared spectra (FTIR), X‐ray diffraction (XRD), scanning electron microscopy (SEM), 1H‐NMR, and pyrolysis mass spectrometry (PMS). It was found that the slight addition of styrene to acrylonitrile strongly changes crystallinity, morphology, and thermal decomposition of the resulting polymer. 1H‐NMR measurment of AN/St copolymer showed the appearance of aromatic proton signals and shifted the resonance of the methylene proton to lower chemical shifts. The mass spectra of AN/St copolymers showed fragments of pyrolysates corresponding to oligonitriles with styrene end groups. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 268–275, 2002; DOI 10.1002/app.10324  相似文献   

18.
Poly(methyl methacrylate‐co‐styrene) composite latices were prepared by thermally initiated seed emulsion (co)polymerization of styrene (ST), methyl methacrylate (MMA), or ST and MMA employing a PST or PMMA seed in the absence of conventional initiators. The changes of particle morphology, observed by transmission electron microscopy (TEM), were investigated by varying seed particle component, the weight ratio of monomer to seed polymer, monomer composition, and employing preswelling of the seed particles. The size distribution of polymer particles obtained from thermally initiated emulsion (co)polymerization was improved by employing the seed process. Hemisphere‐like, sandwich‐like, core‐shell, and inverted core‐shell particle morphologies were observed depending upon the polymerization conditions. The preswelling of seed particles did not affect the morphology of final particles. The particle morphologies, obtained from the thermal process, were compared with those obtained from conventional seed emulsion polymerization. The incorporation of an initiator fragment SO to polymer chain ends seemed to allow the PST chains to gain some hydrophilicity. From the observation of particle morphology, the hydrophilicity of involved polymers were in the following order: PMMA with ionic (? SO) chain ends > PMMA with no ionic ends > PST with ionic ends > 60% MMA P(MMA‐co‐ST) with no polar ends > 40% MMA P(MMA‐co‐ST) with no polar ends > PST with no polar ends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1737–1748, 2002; DOI 10.1002/app.10581  相似文献   

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环氧丙烯酸酯复合乳液的合成与研究   总被引:1,自引:0,他引:1  
采用半连续种子乳液聚合法制备环氧-丙烯酸酯复合乳液。研究了乳化剂种类及用量、引发剂用量、环氧树脂用量及功能单体用量对乳液及其涂膜性能的影响,通过FTIR、DSC对乳液进行了分析和表征。  相似文献   

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