脂肪醇对聚硅氧烷乳液稳定性的影响

以八甲基环四硅氧烷、N-β-氨乙基-γ-氨丙基二甲氧基基硅烷等为原料，在氢氧化钾催化作用下，通过开环共聚合成了聚硅氧烷乳液，并就稳定剂长链脂肪醇对乳液稳定性的影响进行了较详细的研究，得到了较佳的合成工艺。     

A convenient method for preparation of hydroxyl silicone oils with ring opening polymerization of octamethylcyclotetrasiloxane (D4)

Hydroxyl silicone can be prepared at a mild polymerization temperature with a moderately high yield via ring opening polymerization of D4 catalyzed by rare earth solid super acid SO₄^2?/TiO₂/Ln³⁺. The outstanding advantage of the method was that the viscosities of the products can be conveniently controlled by adjusting polymerization time, temperature, and the amount of water. The products were characterized by size-exclusion chromatography, ¹H-nuclear magnetic resonance, and Fourier transform-infrared spectroscopy. A cationic coordination-insertion polymerization mechanism was also proposed.     

A Global Model of Chemical Vapor Deposition of Silicon Dioxide by Direct-Current Corona Discharges in Dry Air Containing Octamethylcyclotetrasiloxane Vapor

A model of the electron distribution in direct current corona plasmas is combined with a global chemistry model and a two-dimensional transport model to predict the rate of chemical vapor deposition of silicon dioxide on the discharge wire in both positive and negative discharges in dry air containing octamethylcyclotetrasiloxane. The gas-phase chemistry includes reactions to form atomic oxygen (O) and additional global reactions to form gaseous silicon dioxide precursors by the impact reactions of electrons and atomic oxygen with silicone molecules. Surface chemistry is approximated by a single step global reaction from gaseous to solid silicon dioxide. The rate coefficient between atomic oxygen and octamethylcyclotetrasiloxane is estimated from prior experiments to be on the order of 10^–12 cm³/molecule-s. The effects of discharge polarity, current, wire radius and air velocity (Peclet number for mass transfer) on the deposition rate are considered. Deposition rates can be minimized by using positive coronas instead of negative coronas for Peclet number less than 18.5. At higher Peclet numbers, the deposition rate is slightly higher in positive corona discharges, but devices used indoors should continue to use the positive corona in order to minimize the production of ozone. The deposition rate in the positive corona is relatively insensitive to air velocity for velocities from 0.044 to 10 m/s^–1 . However,it may be minimized by operating the corona with the lowest current that provides adequate performance (e.g., particle charging) and the smallest wire that provides adequate mechanical strength.     

Ring-opening polymerization of octamethylcyclotetrasiloxane using 3d metal trifluoroacetate complexes

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新型氨烃基聚硅氧烷的制备与表征

以八甲基环四硅氧烷(D4)、N,N-二甲基-γ-氨丙基-γ-氨丙基甲基二甲氧基硅烷(KH-S i-121)和六甲基二硅氧烷(MM)为原料,在硅醇钾催化剂存在下,采用本体聚合反应合成了一种新型氨基聚硅氧烷———N,N-二甲基-γ-氨丙基-γ-氨丙基聚二甲基硅氧烷(ASO-121).最佳合成条件为:60.32 g D4,4.85 g KH-S i-121,0.10 g MM,硅醇钾用量0.11%(占单体总质量分数),D4开环聚合反应温度为115~120℃,反应时间为8 h,可得一定黏度(或相对分子质量)的氨烃基聚硅氧烷.用红外、核磁共振氢谱对其结构进行了表征.     

甲基氢硅氧烷/二甲基硅氧烷二元共聚物及其齐聚氧化乙烯接枝物的合成

本文采用质子酸催化剂合成出含Si-H键的线型聚(甲基氢硅氧烷/二甲基硅氧烷)中间体。讨论了体系中微量水、封端剂用量及产物处理方法对聚合物分子量的影响。将此中间体与α-烯丙基齐聚乙二醇甲醚反应,NMR和IR结果均表明得到了带有氧化乙烯结构侧链的硅氧烷接枝共聚物。     

阴离子本体共聚合成氨基硅油的研究

通过阴离子本体共聚合成了氨基硅油，考察了温度、催化剂浓度，促进剂及原料单体配比对共聚过程的影响并分析了共聚反应机理。     

Synthesis of α,ω-arylamine functionalized poly(dimethylsiloxane)s

This research has focused on the development of telechelic, aromatic amine functional, poly(dimethylsiloxane) oligomers without any aliphatic components in the polymer backbone. The intent is to produce flexible oligomers with enhanced thermal stability for incorporation into materials which will be processed at elevated temperatures. The poly(dimethylsiloxane)s have been synthesized using living polymerization of hexamethylcyclotrisiloxane with protected aniline derivatives as initiators and termination reagents for the reactions. Low molecular weight oligomers prepared using the living polymerization method can be easily converted to a range of higher, controlled molecular weight materials in redistribution reactions. A basic tetramethylammonium siloxanolate catalyst in conjunction with octamethylcyclotetrasiloxane has been used for the equilibration procedure. © 1993 John Wiley & Sons, Inc.     

氨基聚硅氧烷的合成

通过八甲基环四硅氧烷,Ｎ－β－氨乙基－γ－氨丙基甲基二甲氧基硅烷等原料氢化钾催化和促进剂作用下,低温开环共聚得到一系列不同氨值不同粘度的氨基聚硅氧烷,利用ＩＲ、＾１Ｈ－ＮＭＲ对其结构进行表征。对影响反应的因素进行了较详细的研究,得到较佳的合成工艺。