三氯乙酸刻蚀法观测尼龙球晶形态

筛选出特效刻蚀剂——三氯乙酸溶液,建立了简便、可靠且十分有效的表征本体尼龙-6球晶形态的方法,借助SEM首次对MC尼龙及其改性样品的结晶形态进行了直接观测,三维结构的球晶清晰可见,球晶直径为几十微米.利用三氯乙酸及其溶剂与各种添加剂的物理或化学作用,可有效地研究改性尼龙的球晶缺陷.     

温度对含硅聚酰亚胺膜气体分离性能的影响

合成了次联苯基型合硅聚酰亚胺（ＳＩＤＡ－ＢＤＡ），研究了其均质膜对Ｈ２，Ｏ２和Ｎ２的透过分离性能与温度的关系，随着温度的升高，气体的透过系数和扩散系数增大，而溶解系数和选择系数则降低，此外，我们还讨论了气体在膜中的透过活化能，扩散活化能和吸着热。     

聚-1,3,5-三嗪的合成及性能

将联苯二脒与苯甲醛或其盐酸盐与乙酸酐进行缩聚反应,合成了两种新的聚-1,3,5-三嗪,用元素分析、红外光谱、差热分析及热重分析进行了表征,聚合物的η_(比粘)为0.46—0.56分升/克(1％硫酸,25℃),具有良好的耐温性和耐水解性,也有一定的溶解性,利用这种聚-1,3,5-三嗪和二氯化钯反应,可以制成新的高分子络合物。     

SYNTHESIS OF SILICON MONOMERS AND OLIGOMERS CONTAINING CYCLOHEXYLENE RING

1,3-Bis(trichlorosilyl) cyclohexane was obtained by addition of HSiCl_3, to cyclohexadiene-1,3in the presence of H_2PtCl_6.6H_2O in isopropyl alcohol. The new compound was ethanolysed andmethylated to form di-methyl tetra-ethoxy disilyl, tri-methyl tri-ethoxy disilyl and terta-methyldi-ethoxy disilyl cyclohexanes. These di-to tetra-functional monomers were hydrolyzed by hydrochloric acid in ether. The di-functional monomer yielded cyclic dimer similar to octamethylcyclotetrasiloxane and the tri-functionalmonomer, a cyclic tetramer, while in the case of tetra-functional monomer a cyclic octamer wasobtained. These compounds have not been reported in literature.     

聚酰亚胺和聚苯基喹噁啉的水解研究

聚酰亚胺和聚苯基喹嘿啉同属耐高温高分子,热氧化稳定性能好,但前者的耐水解性能却比后者逊色得多。本文对它们的模型化合物作了量子化学计算,对模型化合物和高聚物分别进行了水解反应,从理论上和实验方面都证实了聚酰亚胺是不耐水解的,而聚苯基喹嗯啉的耐水解性却十分突出。     

几种新型的耐高温耐水解的聚苯基-1,2,4-三嗪

由对苯二酰胺腙和五种不同的芳族四酮分别进行缩聚反应,可以合成五种新的聚苯-1,2,4-三嗪,对它们进行了表征。η_(比粘)介于1.39—2.16分升/克范围内。这些高聚物可以浇铸成韧性的薄膜,涂制成漆包线,具有良好的耐温性、耐水解性、耐溶剂性、电绝缘性及力学性能等。     

STUDY ON HYDROLYSIS OF POLYIMIDE AND POLYPHENYLQUINOXALINE

Although polyimide (PI) and polyphenylquinoxaline (PPQ) are both heat resistant polymers, their hydrolytic stabilities are quite different. In this paper, the electron densities of two model compounds——N-phenylphthalimide and 2,3-diphenylquinoxaline are calculated by moans of CNDO/2 method. On the other hand, hydrolysis of model compounds and polymers is carried out. The theoretical calculation and experiments both prove that PPQ has excellent hydrolytic stability while PI is completely hydrolyzed under the same experimental condition. The mechanism of hydrolysis is also predicted.     

SYNTHESIS AND PROPERTIES OF POLY-1,3,5-TRIAZINES

Two new polytriazines: poly[2-methyl-4, 6-(4,′4″-diphenylene)-1, 3, 5-triazine] (Ⅰ) and poly[2-phenyl-4, 6-(4′, 4″-diphenylene)-1, 3, 5-triazine] (Ⅱ) were synthesized from the solution condensation of biphenyl-4, 4′-diamidine dihydrochloride with acetic anhydride and biphenyl-4, 4′-diamidine with benzaldehyde respectively. These two polymers were characterized by TGA, DTA, elemental analysis and IR spectroscopy. They exhibited good thermal oxidative stability as shown by the fact that the powders of these polymers suffered 5.4%, 2.4% weight loss after isothermal aging in air at 300℃for 200 hours. The decomposition temperature of (Ⅱ) was 583℃in air and 590℃in N_2. These linear poly-1, 3, 5-triazines were soluble in concentrated sulfuric acid, phosphoric acid and trifluoroacetic acid whereas the erosslinked poly-1, 3, 5-triazines reported in the literature were insoluble and infusible.It is interesting that these polymers can form complexes with metal halides as determined by X-ray photoelectron spectroscopy (XPS). The polymer metal complex (Ⅲ). PdCl_2 possesses catalytic activity for hydrogenation.     

SYNTHESIS AND PROPERTIES OF POLYPHENYLQUINOXALINES CONTAINING CHLORO-ATOM

Several polyphenylquinoxalines (PPQ's) containing chloro-atom in the side chain have been syn-thesized and characterized by IR, TGA, ITGA and DTA. High quality, flekible, glass-cast films andvarnished wires have been obtained. The T_g's values and thermal stabilities of these polymers wereguater than those without any chloro-atom substitutent.     

催化剂用量对MC尼龙合成、形态与性能的影响

本文通过改变催化剂用量合成了三个系列MC尼龙,对其球晶形态及部分性能进行了表征.引发剂和活化剂用量对聚合速度,单体转化率和产物熔融指数都有很大影响.为保证MC尼龙有优良的综合性能,催化剂用量须控制在一定的范围内,减少催化剂用量是提高其抗冲击强度的有效途径.