醋酸乙烯-丙烯酸无皂乳液共聚的研究

以醋酸乙烯(VAc)为主单体,丙烯酸(AA)为改性功能单体,以半连续加料方式进行无皂乳液共聚过程,得到了稳定且固含量为30%左右的乳液。探讨了功能单体AA含量、反应温度等对共聚的影响。采用FT-IR、粒径分析等方法对共聚物的组成、乳胶粒子的尺寸及分布进行了分析表征。结果表明:在(65±2)℃下聚合,所得乳液稳定性好、转化率高、反应完全,且随着功能单体AA含量的增加,乳液黏度上升、单体转化率下降、乳胶粒粒径变小且粒径呈单分散性。     

改性聚醋酸乙烯酯乳液胶粘剂的研究进展

综述了国内外改性聚醋酸乙烯酯乳液胶粘剂的研究进展,并对聚醋酸乙烯酯乳液胶粘剂的改性研究提出了一些建议和展望。     

Specificity of the pheromone system ofAdoxophyes orana andClepsis spectrana

The pheromone system of the summer fruit tortrix mothAdoxophyes orana (Fischer von Röslerstamm) consists of a mixture ofcis-9- andcis-11-tetradecen-1-ol acetate (cis-9- andcis-11-TDA, respectively) in a ratio of 9:1. Substitution of one or both of these compounds by related unsaturated acetates reduced the attractancy. Onlycis-11-TDA could be replaced bycis-11-tridecen-1-ol acetate (cis-11-TriDA), although the 9:1 mixture ofcis-9-TDA andcis-11-TriDA was less attractive in the field than the pheromone system itself. The major component of the pheromone system of the leaf rollerClepsis spectrana (Treitschke)(cis-9-TDA:cis-11-TDA=1:9) could also be replaced bycis-11-TriDA, again with some reduction in attractancy.     

Cellulose membranes for reverse osmosis Part I. RO cellulose acetate membranes including a composite with polypropylene

With the aim of obtaining RO membranes for brackish water desalination from purified celluloses (cotton linters and bleached bagasse pulp), two reactions (heterogeneous and homogeneous) were applied for the synthesis of cellulose acetate (CA). The efficiency of the membranes was measured and compared with those prepared from purchased CA and prepared CA by acetylation of imported high-grade viscose wood pulp. The effect of blending CA with polypropylene (PP), on the efficiency of the prepared RO membranes was also studied. Results showed that the method of preparation of CA plays a profound effect on the salt rejection and water flux of the RO membranes. The efficiencies of RO membranes formed from heterogeneously acetylated celluloses are higher than those prepared from homogeneous ones. Blending the acetylated cellulose with 9% PP wastes improves the efficiency of membranes prepared from the homogeneously acetylated celluloses.     

Water flux,DSC, and cytotoxicity characterization of membranes of cellulose acetate produced from sugar cane bagasse,using PEG 600

Summary In this article, cellulose acetate produced through the homogeneous acetylation of sugar cane bagasse cellulose was used to produce membranes, using poly(ethyleneglycol) 600 (PEG 600) as an admixture. The membranes were characterized using water flux measurements (Payne’s cup), differential scanning calorimetry (DSC) and neutral red uptake (cytotoxicity). The results showed that PEG 600 acts as a crystallinity inductor and/or pore former in the cellulose acetate matrix. The induction of crystallinity is important for this system since it had not been reported on the literature yet. The results also demonstrated that the studied membranes present a nontoxic behavior.     

Field trapping of threeEpinotia species with (Z,Z)-7,9-dodecadienyl acetate (Lepidoptera: Tortricidae)

Field survey of the geometrical isomers of 7,9-dodecadienyl alcohol, acetate, and aldehyde has resulted in attractants and inhibitors for three species of tortricid moths.Epinotia silvertoniensis and an undescribedEpinotia sp. were all attracted to (Z,Z)-7,9-dodecadienyl acetate. AnotherEpinotia sp. was attracted to (Z,Z)-7,9-dodecadienyl acetate and (Z,Z)-7,9-dodecadien-1-ol. Electroantennogram data and inhibition patterns for one of theEpinotia sp. are also reported. In addition,E. criddleana was attracted to lures containing (E)-9-dodecenyl acetate.     

Naegeli茶螺烷合成方法的改进

对Naegeli报道的以β-紫罗兰酮为原料经乙酸异丙烯酯酯交换、硼氢化钠还原成逆紫罗兰醇再环化合成茶螺烷的方法进行了改进,改进后的合成方法反应副产物巨豆三烯含量从15%降至4%,反应时间明显缩短,茶螺烷的收率从75%提高至84.5%。     

EVA／木质素薄膜的制备与性能研究

研究了经造粒、吹塑成膜的乙烯醋酸乙烯酯共聚物（EVA）／木质素共混物的结构、热性能以及力学性能。热重分析表明木质素与EVA共混物的热稳定性比单一组分的高；差示扫描量热分析表明木质素与EVA的相容性好；傅里叶红外光谱分析表明木质素与EVA之间存在分子间氢键相互作用；扫描电子显微分析表明木质素含量对共混物形貌有明显的影响；力学性能测试表明木质素含量在30％（质量分数，下同）以内，共混物薄膜仍具有较好的力学性能，随着木质素含量的增加，共混物力学性能降低。     

原位生成甲基丙烯酸钠增强EVM硫化胶的性能

通过氢氧化钠（NaOH)和甲基丙烯酸（MAA）的中和反应，在乙烯－乙酸乙烯酯橡胶（EVM）中原位生成甲基丙烯酸钠（NaMAA)，研究了NaMAA原位增强EVM的流变特性，应力软化和应力松弛以及老化前后的力学性能，并与炭黑（N330）增强的硫化胶进行对比，结果表明：NaMAA的引入对EVM混炼胶的门尼粘度几乎没有影响，但在硫化过程中提高了混炼胶的硫化速度，缩短了焦烧时间，与HAF相比，NaMAA对EVM硫化胶具有更好的增强效果，较好的耐老化性能，NaMAA增强的EVM硫化胶具有更明显的应力软化效应，应力松弛程度更大。     

水溶液型醋酸钴催化剂的工业运用研究

本文介绍了水溶液型醋酸钴催化剂在仪化年产33万t的PTA装置上的试用情况,试用过程中发现催化剂中黑色沉淀物可以抑制PX氧化主反应,促进燃烧副反应,影响产品质量和装置正常操作。