排序方式: 共有21条查询结果,搜索用时 62 毫秒
1.
将甲基三氯硅烷和二甲基二氯硅烷分别与二苯基二羟基硅烷反应得到1,1,5,5-四氯-1,5-二甲基-3,3-二苯基三硅氧烷(A)和1,1,5,5-四甲基-1,5-二氯-3,3-二苯基三硅氧烷(B)。按一定比例将(A)和(B)水解缩合得到完全是甲基硅羟基封端树脂(Ⅰ)。将甲基三氯硅烷和甲基三乙酰氯基硅烷分别处理一般共水解法硅封端树脂可得到另外两种甲基硅羟基封端树脂(Ⅱ)和(Ⅲ),将树脂Ⅰ、Ⅱ、Ⅲ与一般共水解法得到的具有相同R/Si和Ph/R(R代表甲基和苯基)的树脂(Ⅳ、Ⅴ、Ⅵ)进行固化试验,结果表明,甲基-硅羟基封端树脂(Ⅰ—Ⅲ)的固化速度为共水解法制得的以苯基硅羟基封端树脂(Ⅳ—Ⅵ)固化速度的两倍以上。 相似文献
2.
A novel reactive polyorganosiloxane containing nitro groups was first prepared by acid-catalyzed equilibration polymerization. The monomer, 3-(4-nitrophenoxy)propylmethyldichlorosilane (NPPMS), was synthesized by hydrosilylation reaction with dicyclopentadienylplatinum(II) chloride (Cp2PtC12) catalyst in high yield. The synthesized polynitroorganosiloxane, which has potential application as a precursor for synthesizing advanced functional polymers, was characterized by FTIR, 1H-NMR, 13C-NMR, 29Si-NMR, vapor pressure osmometry (VPO) and gel permeation chromatography (GPC). 相似文献
3.
A novel soluble ladderlike polysilsesquioxane containing reactive ester groups (Ester-T) was synthesized for thefirst time by stepwise coupling polymerization including preammonolysis, controlled hydrolysis and polycondensation. Themonomer, 3-trichlorosilylpropoxy 4-acetoxybenzoate (M), was synthesized by hydrosilylation of allyloxy 4-acetoxybenzoatewith trichlorosilane in the presence of dicyclopentadienylplatinum (II) chloride (Cp_2PtCl_2) catalyst. Combination of FTIR,~1H-NMr, ~(13)C-NMR, ~(29)Si-NMR, XRD, DSC, TGA and VPO methods was used to demonstrate that the polymer obtained hasan ordered ladderlike structure. The synthesized Ester-T may have promising applications as a precursor of advanced functional polymers. 相似文献
4.
The one plus one (1 + 1) mode of hydrosilation reaction of ladderlike cis-isotatic polyallylsilsesquioxane (Allyl-T)and polyhydrosilsesquioxane (H-T) using dicyclopentadienylplatinumdichloride (Cp_2PtCl_2) as the catalyst leads to theformation of a new polyorganosiloxane (POS). The presence of nanoscale tubular structure in the product POS waspreliminarily proved by IR, ~1H-NMR, differential scanning calorimetry (DSC), X-ray diffraction (XRD), gel permeationchromatography (GPC), atomic force microscopy (AFM) and molecular simulation. 相似文献
5.
By covalently binding chromophore NPP, N-(4-nitrophenyl)-(L)-prolinol, to a structurallycontrolled cage-like cross-linking polymer (SCCP), a modified nonlinear optical (NLO) polymeric filmprepared by "in situ poling and sol-gel" process successfully overcame the fundamental problem of NPPchromophores subliming out from the cages of the "doped" NLO polymeric film when heated or placed underUV light. Its d_(33) (coefficient of second harmonic generation) is 2.0×10~(-8) esu. measured by IR dichroism. Themodified film has a low decay of the SHG signal and preserves 94% of the initial value after 50 days at roomtemperature. These properties match that of the "doped" film, indicating that the modified film also retainsthe main advantages of the "doped" film. 相似文献
6.
Neal Tai-sheng Chung 《高分子科学》2000,(5):459-463
Ladderlike polychloropropylsilsesquioxane (CP-T) was first synthesized by "stepwise coupling polymerization".The molecular weight of CP-T is as high as 1.7×10~5. It is a tough, elastic reactive ladderlike polymer and has good heat-resistant and adhesive properties. CP-T can further react with many nucleophilic reagents to generate new ladderlike reactivepolysilsesquioxanes, which can be used as potential precursors in the synthesis of functional ladderlike polymers. 相似文献
7.
Fluorescence spectra of ladderlike polyphenylsilsesquioxane (LPPS) and ladderlike 1,4-phenylene-bridgedpolyvinylsiloxane (LPPVS) have been measured as a function of temperature (4-55℃), in dilute tetrahydrofuran solution.The excimer (I_E) to monomer (I_M) intensity ratio (I_E/I_M) of LPPS dilute solution shows a double linear Arrhenius plot with abreak point ascribable to a transition temperature T_t This behavior has not been found for single chain polyorganosiloxanes.When InI_E of LPPS was plotted against I/T it also gave a double linear plot with one break point, which was found in singlechain polyorganosiloxanes. The different behaviors between LPPS and single chain polyorganosiloxanes may be mainlyattributed to the relatively rigid double-chain macromolecular backbone of LPPS. However, the In(I_E/I_M) of dilute LPPVSsolution versus I/T shows a simple linear variation with a positive slope which confirms our proposition. The differencebetween the fluorescence results of LPPS and those of LPPVS may possibly derive from their structure differences andcooperative motion in backbone chain bonds. 相似文献
8.
Heat-resistant silicone gels were synthesized by replacing the single main chain polymethylhydrosiloxane withreactive ladderlike polyhydrosilsesquioxane copolymers. Because of the interaction between polydimethylsiloxane chainsand the ladderlike polysilsesquioxanes chains, the cyclization of the polydimethylsiloxane chains is hindered. The highthermal stability of the ladderlike polymers can improve the thermal stability of the silicone gels without sacrificing their good comprehensive properties. 相似文献
9.
Chun-qing Liu Yang Liu Zhong-rong Shen Ping Xie Rong-ben Zhang Chao-bin He Tai-shung Chung 《高分子科学》2001,(1):97-102
A novel alcohol-soluble polyorganosiloxane containing amino side groups, poly[3-(4-aminophenoxy)propylmethylsiloxane] (2), was first prepared by the reduction of nitro groups on 4-nitrophenoxypropyl side chains of poly[3-(4-nitrophenoxy)propylmethylsiloxane] (1). The reaction proceeded easily with nearly 100% conversion. The synthesized alcohol-soluble polymer 2, which has potential application as a precursor for preparing advanced functional polymers, was characterized by FTIR 1H-NMR, 13C-NMR, 29Si-NMR, VPO and GPC, respectively. 相似文献
10.
Huai-zhong Pan Chun-qing Liu Zhong Jin Ming Cao Jian-hua Luo Ping Xie Rong-ben Zhang Yu-hui Lin Neal Tai-sheng Chung Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing China Institute of Materials Research Engineering Singapore Singapore 《高分子科学》2000,(5):453-457
Ladderlike polyhydroxypropylsilsesquioxane (HO-T) was synthesized by alcoholysis of ladderlike poly(3-propionyloxy-propyl)silsesquioxane. The HO-T was characterized by GPC, IR, NMR, DSC, TGA and X-ray diffractionmethods. Through hydrogen-bonding interaction, ladderlike polymer (HO-T) can form a supramolecular complex withsomewhat regular structure. 相似文献