PSt／PBA胶乳型互穿聚合物网络性质的研究

用乳液聚合技术制备了ＰＳｔ／ＰＢＡ胶乳型互穿聚合物网络，着重讨论了乳化剂、引发剂、交联剂及加料方式对其性能的影响。     

天然橡胶胶乳热稳定性测定方法

论述了几种天然橡胶胶乳热稳定性测定方法的特点及其在应用上存在的问题，指出了进一步研究胶乳热稳定性测定方法的必要性     

天然橡胶中脂肪酸的分析与研究

天然橡胶和复合橡胶在许可证管理和关税税率方面存在较大的差异,使海关对复合橡胶的进口监管面临着较大风险。本方法紧贴海关监管要求,利用气相色谱和溶解法对天然橡胶中的各种脂肪酸进行分析和测定,通过对比天然橡胶加入工业硬脂酸后制成的复合橡胶中脂肪酸的变化,对添加工业硬脂酸的复合橡胶进行定性分析。     

PVAc／PS／PnBA三元乳胶IPN的合成及相容性研究

用分步乳液聚合法合成了聚醋酸乙烯酯/聚苯乙烯/聚丙烯酸丁酯(PVAc/PS/PnBA)三元乳胶互穿聚合物网络(IPN)。用IR、DMS对体系进行了表征。研究发现,体系中各组分的相容性不好。对相容性较差的原因进行了探讨。     

Synthesis and properties of grafted latices from a soybean oil‐based waterborne polyurethane and acrylics

A novel soybean oil‐based vinyl‐containing waterborne polyurethane (VPU) dispersion has been successfully synthesized from toluene 2,4‐diisocyanate, dimethylol propionic acid and a 90 : 10 mixture of chlorinated soybean oil‐based polyol and acrylated epoxidized soybean oil (AESO). Then, a series of VPU/acrylic grafted latices have been prepared by emulsion graft copolymerization of acrylic monomers (40 wt % butyl acrylate and 60 wt % methyl methacrylate) in the presence of the VPU dispersion, using potassium persulfate as an initiator. The structure, morphology, and thermal and mechanical properties of the resulting latices, containing 15–60 wt % soybean oil‐based polyols as a renewable resource, have been investigated by Fourier transform infrared spectroscopy, solid state ¹³C NMR spectroscopy, transmission electron microscopy, thermogravimetric analysis, dynamic mechanical analysis, and mechanical testing. The results indicate that graft copolymerization of the acrylic monomers onto the VPU network occurs during emulsion polymerization, leading to a significant increase in the thermal stability and mechanical properties of the resulting miscible grafted latices. This work provides new environmentally‐friendly latices from a renewable resource with high performance for coating applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

丁苯乳液改性水泥混凝土弯曲性能研究

研究了丁苯乳液掺量对混凝土压折比、最大弯曲荷载挠度、弯曲韧性系数等弯曲性能的影响以及相互之间的关系。结果显示乳液掺量由0提高至60%时,混凝土的抗弯拉强度与弯曲韧性系数呈现先提高后降低的现象;当乳液掺量为17%时,混凝土的抗弯拉强度达到最大值7.54 MPa,而当乳液掺量为19%时,混凝土的弯曲韧性系数达到2.029;混凝土最大弯曲荷载对应挠度值随乳液掺量的增加则大致呈现线性增大的变化趋势;而压折比呈现先降低后升高的变化规律,在丁苯乳液掺量为19%时达到最小值。弯曲荷载-挠度曲线特征显示改性后混凝土弯曲变形能力随乳液掺量的增加而逐渐增强,综合考虑聚合物乳液的成本,建议丁苯乳液的最佳掺量为13%~15%。经过数据归纳分析,当乳液掺量≤21%时,压折比、最大荷载挠度随弯曲韧性系数的提高而分别呈指数降低、线性增加。     

Investigation of crude latex from various Carica papaya varietices for lipid bioconversions

The protein contents in crude latices from various varieties of papaya (Carica papaya) and their catalytic activities in proteolysis, lipolysis, and interesterification reactions were studied with regard to the variety, the geographic location of cultures, and the frequency of fruit tapping. Biocatalytic activities of these raw materials were compared to several commercially available crude and purified preparations of papain. These investigations were carried out in order to have a better physicochemical characterization of these raw materials, to select the adequate papaya latex for protein or lipid bioconversions, and to valorize them on an industrial scale. For the purified preparations of papain, only proteolytic activity was obtained. All crude papaya latices exhibit proteolytic, lipolytic, and interesterification activities, and no relationship between the proteolytic and lipolytic activities was observed. The high multiple correlation coefficient (R) on the order of R=0.93–0.99, obtained from the regression analysis for the lipolytic and interesterification activities for all crude papaya latices investigated suggested that there was a correlation between these enzyme activities. However, for the same lipase preparation, the interesterification activity differed substantially depending on the type of interesterification reaction.     

低毒性接枝氯丁胶粘合剂的制备和发展

综述了低毒性溶剂型接枝氯丁胶粘合剂的研究现状及接枝氯丁胶粘合剂的发展方向     

搅拌对丁苯吡乳液聚合的影响

研究了搅拌对丁苯吡（简称ＶＰＬ）乳液聚合的影响。通过实验考察了不同搅拌器型式（折叶涡轮和Ｂｒｕｍａｇ－ｉｎ桨）和搅拌强度对ＶＰＬ浮液聚合流体混合、聚合反应速率、胶乳粒径和聚合稳定性的影响。结果表明,折叶涡轮搅拌器不适合ＶＰＬ乳液聚合,而Ｂｒｕｍａｇｉｎ桨比较适合ＶＰＬ乳液聚合;在ＶＰＬ乳液聚合中存在着最佳搅拌速度范围,并提出了最佳的搅拌控制方法。     

甲基丙烯酸甲酯与降解天然橡胶胶乳共聚的研究

研究了不同降解程度的天然橡胶胶乳与甲基丙烯酸甲酯 (MMA)共聚反应 ,发现随着降解时间增长 ,共聚物中 MMA聚合链与橡胶段的相对比例 (重量比 )明显增加。找到了一种适用于降解胶乳与 MMA共聚混合物的分离方法