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双环戊二烯马来酸单酯(DHCM)是一种新型的功能性单体,用于改性不饱和聚酯树脂不仅具有优异的气干性和低收缩率,而且产品色泽较浅,无胶凝颗粒、贮存稳定性好。该文研究了以顺丁烯二酸酐(MA)、双环戊二烯(DCPD)和水为原料合成DHCM的工艺,探讨了原料配比、催化剂种类、反应温度和反应时间等因素对DHCM收率及产品中w(DHCM)的影响,并通过正交实验及红外、GC-MS等进行了表征,确定了优化的工艺条件:原料摩尔比n(MA)∶n(H2O)∶n(DCPD)=1.0∶1.0∶1.0,反应温度125℃,催化剂为醋酸钠,反应时间2.5 h。在该条件下,DHCM的收率为90%,产品中w(DHCM)>85%。 相似文献
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研究了在无催化剂无溶剂条件下合成顺丁烯二酸单辛酯和苯酐单辛酯的工艺条件 ,通过控制反应温度和反应时间 ,制备了产率较高的目标产物。采用了一种简便的碱滴定法测定产物的酸度值来确定产物的质量分数和产率 相似文献
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双环戊二烯马来酸酯的合成工艺及应用 总被引:1,自引:0,他引:1
双环戊二烯、顺丁烯二酸酐及水在135~140℃经水解、加成反应即生成双环戊二烯顺丁烯二酸单酯(DHCM),该产品可用于不饱和聚酯及醇酸树脂的改性,使之具有气干性。另外,还可改进其耐热、耐化学腐蚀等性能。 相似文献
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聚双环戊二烯反应注射成型研究—聚双环戊二烯的合成研究 总被引:3,自引:0,他引:3
以WCl5/WOCl4.为催化剂,AlEt3为活化剂,在温度为70~100℃的条件下采用RIM方法完成了双环成二烯的聚合反应.考察了催化剂用量、活化剂用量、反应温度对上述反应的影响,并对聚合物的IR谱图进行了研究,测定了聚合物中C=C键的含量.实验结果表明.双环戊二烯的聚合反应是一易位开环反应. 相似文献
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醋酸乙烯-单丙烯酸环氧酯乳液共聚的研究 总被引:1,自引:2,他引:1
本文报导了一种新型醋酸乙烯-单丙烯酸环氧酯共聚物的研制。该化合物由于含有单丙烯酸环氧酯链节,因此能有效地改进聚醋酸乙烯的耐水性和有高的粘结强度。此外还用物理和化学方法测定了单丙烯酸环氧酯和共聚物的结构。 相似文献
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双环戊二烯(DCPD),分子式为C_(10)H_(12), 分子量为132.21。该品是环戊二烯(CPD) 的二聚体,将CPD置于室温下容易二聚化作 用生成二聚体环戊二烯(DCPD),将本品 加热到140~160℃,能发生可逆反应,解聚 成CPD,反应式如下: 相似文献
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The influence of recipe and process conditions on the coagulation behavior of polystyrene (PS) and polyvinyl acetate (PVAc) latices has been studied. Seeded batch experiments reveal a significant influence of electrolyte concentration on the coagulation behavior of both PS and PVAc latices. Within the experimental error, no dependency of the coagulation behavior on process conditions, in terms of energy dissipation, reactor scale, impeller type, and impeller diameter, has been observed for the reactor scales investigated. These results indicate that intrinsic chemical influences such as electrolyte concentration dominate the coagulation behavior during emulsion polymerization and also in the absence of polymerization over the process conditions. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 2409–2421, 1998 相似文献
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本文尝试用聚丙烯酰胺、羧甲基纤维素及乙基纤维素代替聚乙烯醇作醋酸乙烯乳液聚合的保护胶体。实验结果显示,聚丙烯酰胺、乙基纤维素可以作为醋酸乙烯乳液聚合的保护胶体。本文对所得乳液的物化性质尚未进行详细研究。 相似文献
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氯乙烯-丙烯酸酯-醋酸乙烯酯三元共聚乳液的研究开发 总被引:1,自引:0,他引:1
采用乳液接枝共聚和核壳聚合相结合的工艺,用十二烷基硫酸钠作为新型种子乳化剂合成氯乙烯-丙烯酸酯-醋酸乙烯酯接枝共聚乳液,该乳液经Autosizeu IIC型激光粒径仪和DSC曲线测定具有核壳结构特征,用于纺织织物涂层,各项指标完全达到产品所规定的标准,效果很好。 相似文献
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采用乙酸乙烯酯(VAc)在水中以过硫酸钾(KPS)和亚硫酸氢钠氧化还原体系作为引发剂进行无乳化剂乳液聚合,探讨了引发剂浓度、聚合温度、单体浓度和搅拌速度对聚合速率及转化率的影响。结果表明:当VAc质量分数为30%,KPS:VAc摩尔比为1:2 000,聚合温度10℃,反应时间10 h,搅拌速度80 r/min,时聚合产物聚乙酸乙烯的聚合度达到10 848;当VAc质量分数为35%时,聚合转化率可达到96%,聚合速率与引发剂浓度的0.944次方成正比;当搅拌速度达到200 r/min以上时,搅拌速度对聚合速率以及转化率影的响可以忽略。 相似文献
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High-molecular weight (HMW) poly(vinyl alcohol) (PVA) was prepared via an emulsifier-free emulsion polymerization of vinyl acetate (VAc) using a redox initiation system in low temperatures, and the subsequent saponification with potassium hydroxide in methanol. The effect of the polymerization conditions on the conversion, molecular weight, and branching degree was investigated. PVA with maximum viscosity-average degree of polymerization (DP) of 8270 could be prepared by saponification of poly(vinyl acetate) (PVAc), with DP of 10,660 obtained at temperature of 10°C, monomer concentration of 30%, potassium persulfate molar ratio to monomer of 1/2000, agitation speed of 160 rpm. The conversion was above 90%. From the emulsifier-free emulsion polymerization of VAc in low temperature, PVAc with HMW and high linearity was effectively prepared, which might be useful for the preparation of high-strength and high-modulus PVA fiber. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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Hlne Egret Victoria L. Dimonie E. David Sudol Andrew Klein Mohamed S. El‐Aasser 《应用聚合物科学杂志》2001,82(7):1739-1747
Emulsion polymerizations of vinyl acetate (VAc) with polyvinyl alcohol (PVA) as emulsifier were carried out by both batch and semicontinuous processes. The extent of grafting of vinyl acetate onto the PVA chains was investigated by a new method for separating the various polymer fractions in high solids content latexes. The quantification was carried out by a three‐step separation and selective solubilization of the PVAc latexes. After the separation, the water‐soluble PVA and the solvent‐soluble PVAc components were characterized by gel permeation chromatography and 13C–NMR, from which the accuracy of this method was verified. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1739–1747, 2001 相似文献