Effect of concentration and pH of solutions on the absorbency of polyacrylate superabsorbents

Polyacrylate superabsorbent (PAS) was synthesized by aqueous solution polymerization crosslinked by N,N‐methylene bisacrylamide. The effect of pH and concentration of several solutions on absorbency (Q) of PAS was studied. The results showed that the absorbency increased at first and then decreased with the increase of the solution's pH; the summit of the absorbing curve was attained when pH was about 6.25. The relation between absorbency and pH could be represented by a quadratic equation and the square difference was relatively small. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 494–499, 2003     

水基型聚氨酯改性丙烯酸酯系列胶粘剂的研制

介绍了聚氨酯改性丙烯酸酯水基乳液型系列胶粘剂的制备原料和聚合工艺、原理,研究了产品粘度、流变性、聚合物玻璃化温度、产品固含量及粘接工艺对产品粘接强度等性能的影响。     

聚氨酯-聚丙烯酸酯互穿聚合物网络压敏胶及其耐热性研究

为了提高丙烯酸酯压敏胶的耐热性能,本文采用聚氨酯/聚丙烯酸酯(PU/PAA)互穿聚合物网络(IPN)技术对丙烯酸酯压敏胶进行改性,研制出一种软化点达到125℃左右的耐热压敏胶。分析讨论了不同制备工艺因素对该压敏胶性能的影响,并对其耐热性机理进行了探讨。     

丙烯酸改性水性聚氨酯研究进展

综述了近年来聚氨酯-丙烯酸酯(PUA)复合乳液研究的进展，介绍了各类聚氨酯-聚丙烯酸酯复合乳液的制备方法和性能特点。     

水性纯丙乳液的合成及单体配比对乳液附着性能的影响

以甲基丙烯酸甲酯(MMA)、丙烯酸异辛酯(2-EHA)分别为硬单体、软单体,甲基丙烯酸(MAA)为功能单体,过硫酸铵(APS)为引发剂,十二烷基硫酸钠(SDS)、脂肪醇聚氧乙烯醚(AEO-9)为乳化剂,采用半连续种子乳液聚合方法合成单体配比不同的水性聚丙烯酸酯乳液。利用衰减全反射-傅立叶变换红外光谱、核磁共振氢谱、凝胶渗透色谱、热重分析和动态热机械分析层测定水性聚丙烯酸酯的结构及性能。结果表明：随着硬软单体比的减小,聚丙烯酸酯乳液的粒径约为100nm;聚丙烯酸酯共聚物的低分子量部分,数均分子量约为3万,重均分子量约为5万;乳液膜的热分解温度从327.5℃升高到343.5℃,玻璃化转变温度从21℃降至-3.5℃;乳液的表面张力从39.83mN/m降至36.71mN/m、界面张力从19.01mN/m降至4.87mN/m、接触角从62.6°降到27.8°,附着牢度从50%提高到95%,当硬软单体比为7：13时,乳液的润湿性最好,附着牢度最高,满足乳液在BOPP薄膜上的应用要求。说明提高聚合物中软单体含量有利于提高乳液的润湿性,从而提高乳液的附着力。     

Preparation and properties of reactive polyurethane polyacrylate blends based on carbonyl‐hydrazide reaction

A new reactive polyurethane/polyacrylate (PU/PA) blend was developed by mixing a core–shell polyacrylate latex containing keto groups in shell layer and a polyurethane dispersion incorporating multiple hydrazide groups which was synthesized by introducing the poly‐hydrazide groups into the end of the vinyl‐terminated polyurethane chains. Fourier transform infrared (FTIR) spectroscopy and gel permeation chromatography (GPC) results indicated that poly‐hydrazide groups had been incorporated in the polyurethane chains. Transmission electron microscopy (TEM) micrograph revealed that polyacrylate particles had a clear core–shell structure. The results of FTIR, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) indicated that the crosslinking reaction between two polymer systems had happened and crosslinking structure could effectively improve the compatibility between PA and PU. Thermogravimetric analysis (TGA) and mechanical tests results suggested that crosslinking structure could enhance the thermal stability and mechanical properties of blends. The influence of the PA content and the n(? CO? )/n(? NHNH₂) ratio on the hardness, water resistance, solvent resistance, and gel fraction of the blend films were comprehensively studied. The optimal PA content and n(? CO? )/n(? NHNH₂) ratio was 30% and 1.5:1 in this experiment, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44443.     

聚丙烯酸酯共混改性水性聚氨酯乳液性能研究

自制水性聚氨酯乳液,并采用共混方法制备聚丙烯酸酯改性水性聚氨酯乳液。研究了共混改性涂膜的结构和性能,结果表明,聚丙烯酸酯共混改性水性聚氨酯乳液的涂膜性能比水性聚氨酯乳液涂膜性能有明显的提高。经过机械共混改性后,PU/PA膜的耐热性有了较大的提高,拉伸强度比PU膜大,而膜变硬、断裂伸长率大大降低。     

SLP—801涂料印花粘合剂的合成与应用

探索了反应性乳化剂及低温交联单体在乳液型粘合剂合成中的作用;进行了ＳＬＰ－８０１高效特软型低温自交联涂料印花粘合剂合成与应用工艺的研究。     

交联度对聚丙烯酸盐增稠剂性能的影响

研究了反悬浮法合成聚丙烯酸盐（ＰＡＡＳ）增稠剂过程中,Ｎ,Ｎ－亚甲基双丙烯酰胺（ＭＢＡＡ）用量对ＰＡＡＳ吸水、增稠和流变性的影响。发现随ＭＢＡＡ用量的增加,ＰＡＡＳ的吸水性呈先上升后下降的趋势,并当用量为单体质量的１‰时,ＰＡＡＳ的最大吸不倍率（Ｑｍ）、吸收０．９％氯化钠溶液分别高达１２００、３５０、１００ｇ／ｇ;ＰＡＡＳ水增稠体系的触变指数随ＭＢＡＡ用量的增加而提高：当用量为１‰、１．５‰时,Ｐ     

Swelling behaviors of polyacrylate superabsorbent in the mixtures of water and hydrophilic solvents

The swelling behaviors of polyacrylate superabsorbent in the mixtures of water and hydrophilic solvents, including methanol, ethanol, ethylene glycol, glycerol, acetone, dimethyl formamide, and dimethyl sulfoxide, were investigated. In 20 wt % solvent–water mixture, the superabsorbent with granularity between 40‐ and 80‐mesh could reach swelling equilibrium at 25°C in several hours. It was also found that mixture temperature between 15 and 35°C had little influence on absorbency. Furthermore, the influence of water temperature between 0.5 and 99°C on absorbency was also rather limited when the superabsorbent was swelled by distilled water. The mixture concentration influenced absorbency significantly by changing the solubility parameter of the solvent–water mixture, particularly when the solubility parameter of the solvent–water mixture was < 20. The equilibrium absorbency was very high when the solubility parameter of the mixture was > 20, whereas the absorbing capacity of the superabsorbent was very low when the solubility parameter was < 17.5. The polarity fraction of solvents did not have any obvious influence on equilibrium absorbency, but not enough polarity fraction might affect the absorbing rate. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1331–1338, 2000