氯乙烯-醋酸乙烯酯共聚糊树脂的工业化生产

介绍了国内外氯乙烯-醋酸乙烯酯共聚糊树脂牌号和沈阳化工股份有限公司的氯乙烯-醋酸乙烯酯共聚糊树脂工业化生产技术、产品质量指标及"三废"治理与产品的应用情况。     

氯乙烯—醋酸乙烯酯共聚糊树脂简介

概括地介绍了氯乙烯—醋酸乙烯酯共聚糊树脂国内外简况、制备基本理论与特性、以及具体应用。     

运用正交设计开发氯乙烯-醋酸乙烯酯共聚糊树脂

介绍了开发氯乙烯 -醋酸乙烯酯共聚糊树脂的必要性及生产原料、工艺过程 ,并进行了正交设计优化乳化体系的试验。结果表明 :A3 B3 C2 为最佳条件 ,即当单釜加料主乳化剂 5 5 g,助乳化剂A 2 5 g ,助乳化剂B 8g,制得的氯乙烯 -醋酸乙烯酯共聚糊树脂的B型粘度贮存稳定性最佳 ,主乳化剂投料是影响B型粘度贮存稳定性的重要因素     

氯乙烯-醋酸乙烯酯共聚糊树脂的开发

介绍了国内外氯乙烯一醋酸乙烯酯共聚糊树脂的基本理论、生产状况、产品特性及工艺技术，并详细介绍了沈阳化工股份有限公司的氯醋糊树脂开发的进程、工艺及产品的质量指标。     

氯醋糊树脂的合成试验

通过氯乙烯与醋酸乙烯酯的共聚试验,研究了单体的投料配比、加料工艺、聚合转化率等对氯醋共聚糊树脂中醋酸乙烯酯含量以及树脂性能的影响规律,掌握了在10 L聚合釜中制备高醋酸乙烯酯含量氯醋糊树脂的聚合工艺。     

酯溶性氯乙烯-醋酸乙烯酯共聚树脂的研发生产

对比进口与国产氯乙烯-醋酸乙烯酯共聚树脂的常规性能和应用性能,查找了国产氯醋树脂质量差距;针对氯乙烯和醋酸乙烯酯悬浮聚合过程提出了优化措施,改善了氯醋树脂的颗粒形态和分子组成的均匀度,进而提升了酯溶性等应用性能。     

连续加料工艺对氯乙烯-醋酸乙烯酯共聚树脂性能的影响

对比了采用氯乙烯连续加料和一次性加料工艺生产的氯乙烯-醋酸乙烯酯共聚树脂(简称氯醋树脂)的质量和加工性能,结果表明:采用连续加料工艺生产的氯醋树脂的化学组成均匀,溶解性能和加工性能得到提高。     

悬浮法氯乙烯-醋酸乙烯酯共聚树脂生产技术及进展

介绍了悬浮法氯乙烯-醋酸乙烯酯共聚树脂生产工艺技术,列举了国内氯乙烯-醋酸乙烯酯共聚树脂生产技术的新进展,并指出了其工艺技术发展动态。     

醋酸乙烯酯含量测定方法及其评价

主要对测定乙烯-醋酸乙烯酯共聚物中醋酸乙烯酯单体含量的方法进行了介绍和评价,其中包括化学方法、元素分析法、核磁共振法、红外光谱法、热重法以及裂解法等。其中,化学分析法比较经济准确,可以广泛使用;而红外光谱法和热重分析法可以做出快速而准确的测定,在有条件的情况下可以选择使用。各种方法都有一定的优缺点,可以根据实际情况合理选用。     

氯乙烯-醋酸乙烯酯共聚糊树脂次级粒子特性研究

讨论氯乙烯-醋酸乙烯酯共聚乳液后处理工艺与树脂次级粒子特性间的关系。根据氯醋糊树脂性能特点,调整喷雾干燥器进出口温度,研究干燥工艺条件与树脂次级粒子结构及树脂增塑糊粘度间的关系,乳胶固含量对树脂次级粒子及糊粘度的影响规律,确定合适干燥工艺及乳液含固量,降低树脂糊粘度。对优化条件下制备的氯醋糊树脂颗粒特性、流变性能进行分析和对比,获得良好结果。     

氯醋共聚树脂生产环境空间中酯类物质含量的精密分析

通过改变气相色谱分析条件,提高了氯乙烯-醋酸乙烯酯共聚树脂生产环境空间中醋酸乙烯酯、丙烯酸丁酯、丙烯酸异辛酯分析结果的精密度和分析速度,对安全生产意义重大。     

乙烯-醋酸乙烯-氯乙烯共聚树脂合成试验研究

介绍了在10L聚合釜中合成乙烯-醋酸乙烯-氯乙烯(EVA-g-VC)共聚树脂的试验情况。分别研究了EVA种类及用量、EVA的溶胀方法、助剂对聚合过程和树脂颗粒性能的影响规律,制得的EVA-g-VC共聚树脂的加工性能基本达到了国外同类产品水平。     

Effects of hydrophobic unit and its distribution on solution properties of vinyl pyrrolidone and vinyl acetate copolymer

A series of vinyl pyrrolidone and vinyl acetate copolymers with different monomer ratios and homogeneity in backbone distribution were synthesized and their solution properties studied. In water, the phase diagram curve is concave, with the lower critical solution temperature, due to the cooperation of hydrophobic and hydrophilic hydration. In order to make a substantially homogeneous copolymer, a new method to determine the monomer mole fraction is suggested. When the vinyl pyrrolidone to vinyl acetate mole ratio in the copolymer is close to unity, sequence distribution plays an important part in solution behavior. The more homogeneous the structure, the better the solubility in water, and the higher the cloud point. This is attributed to the balance between hydrophobic and hydrophilic forces in solution. Copolymerization kinetic analysis on monomer conversions and turbidity measurement on poly(vinylpyrrolidone/vinyl acetate) solutions give consistent results to confirm this interpretation. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 345–352, 1999     

聚醋酸乙烯乳液保护胶体的改性

介绍了聚醋酸乙烯乳液保护胶体改性的一些现状和进展。包括聚乙烯醇的缩醛化、酰基化、烷基化、醋酸乙烯共聚物皂化、添加剂改性等方法以及其他保护胶体的应用。     

Starve fed emulsion copolymerization of vinyl acetate and 1‐hexene at ambient pressure

A novel emulsion copolymer of vinyl acetate (VAc) and 1‐hexene was synthesized at ambient pressure. The feeding technique, initiation system and reaction time of the copolymerization were optimized based on molecular characteristics such as the weight contribution of 1‐hexene in the copolymer chains and glass transition temperature (T_g) as well as on bulk properties like minimum film‐formation temperature (MFFT) and solid content. According to nuclear magnetic resonance spectroscopy and differential scanning calorimetry results, the combination of starve feeding and redox initiation, within a reaction time of 4 h, effectively led to the copolymerization at ambient pressure between highly reactive polar VAc monomers and non‐polar 1‐hexene monomers of low reactivity. The copolymer showed a lower T_g and MFFT, and a reasonable solid content compared to the poly(vinyl acetate) (PVAc) homopolymer. The consumption rate, hydrolysis of acetate groups and chain transfer reactions during the polymerization were followed using infrared spectroscopy. Based on the results, the undesirable reactions between the VAc blocks were hindered by the neighbouring 1‐hexene molecules. Tensile testing revealed an improvement in the toughness and elongation at break of VAc–1‐hexene films compared to PVAc films. © 2014 Society of Chemical Industry