摘要:
The invention concerns the synthesis of silicone by anionic polymerisation of cyclic organosiloxane oligomers in the presence of a slightly nucleophilic strong base. The invention aims at providing novel strong base catalysts, more efficient in terms of solubility in the silicones, with hydrolysis stability strength and polymerising capacity. To achieve this, the invention provides for the use of ylides derived from aminophosphonium such as for example that of formula: [Me3N)3P—CHMe2]+, MeO or derived from phosphoranylidenes such as that of formula: [Me3P—HC=Pme3]+, t-BuO. The invention also concerns strong base catalysts as novel products.
摘要:
Chemically stable, perfluorinated, linear or cyclic polyorganosiloxanes (POS), and a process for the preparation thereof. Antifoams, agents for lowering surface tension, dirt repellents, antiadhesives, lubricants, oleophobic and/or hydrophobic agents, coatings and other compositions containing the perfluorinated POS are disclosed.
摘要:
Organometallic boron/nitrogen polymers, precursors of boron nitride, include recurring structural units of the formulae (I) and (II): ##STR1## wherein X is N-R.sup.3, Y is NR.sup.1 R.sup.2 and Z is N-R, in which R, R.sup.1, R.sup.2 and R.sup.3, which may be identical or different, are each a hydrogen atom, an optionally substituted hydrocarbon radical, or an organosilyl or hydrogenoorganosilyl radical and are prepared by reacting (a) at least one cyclic compound (compound A) containing recurring structural units of the formula (1): ##STR2## wherein A is a halogen atom and R is a hydrogen atom, an optionally substituted hydrocarbon radical, or an organosilyl or hydrogenoorganosilyl radical, with (b) at least one compound including at least one boron atom to which two halogen atoms are directly bonded (compound B), and (c) at least one compound containing at least one NH.sub.2 group compound C); the resulting organometallic polymers are facilely pyrolyzed into boron nitride ceramic materials.
摘要:
The present invention relates to a process for preparing a compound comprising at least a urethane group —HN—C(═O)—O, said process comprising a step (E) in which a compound (I) comprising at least an isocyanate functional group —N═C═O is reacted with an organic compound (II) carrying at least a hydroxyl group —OH, said reaction being carried out in a presence of a carbene (III) used as a catalyst.
摘要翻译:本发明涉及至少包含氨基甲酸酯基-HN-C(= O)-O的化合物的制备方法,所述方法包括步骤(E),其中至少包含异氰酸酯官能团的化合物(I) -N = C = O与至少含有羟基-OH的有机化合物(II)反应,所述反应在用作催化剂的卡宾(III)存在下进行。
摘要:
The present invention relates to a process for preparing functionalized polyorganosiloxane (POS) resins comprising units M: (R3SiO1/2) Q: (SiO4/2) and M′: (YaR3−aSiO1/2) and optionally D: (R2SiO2/2) and/or D′: (RYSiO2/2) and T: (RSiO3/2) and/or T′: (YSiO3/2), with, in these units: R=C1-C10 alkyl or a C8-C12 aryl and Y a functional group (e.g.: Si—H),by redistribution of POS resins using POSf bearing functional units M′ and/or D′ and/or in the presence of an acid catalyst of the trifluoromethane-sulfonimide (TFSI) type.The present invention also relates to the aforementioned catalyst system.
摘要翻译:本发明涉及一种制备官能化聚有机硅氧烷(POS)树脂的方法,其包含单元M:(R 3 SiO 2 1/2)Q:(SiO 4 / 2)和M':(Y a a R 3-a SiO 1/2)和任选的D:(R' 和/或D':(RYSiO 2/2)和T:(RS 3 O 3/2) / /> T':(YSiO 3/2/2),在这些单元中:R = C 1 -C 10 >烷基或C 8 -C 12芳基,Y是官能团(例如:Si-H),通过使用POSf承载功能单元M'重新分配POS树脂, /或D'和/或在三氟甲烷 - 磺酰亚胺(TFSI)型的酸催化剂存在下进行。 本发明还涉及上述催化剂体系。
摘要:
An elastomeric composition usable for the manufacture of tires, based on at least (i) a diene elastomer, (ii) an inorganic filler as reinforcing filler and (iii), as (inorganic filler/diene elastomer) coupling agent, a organosilicon compound which is at least bifunctional and can be grafted on to the elastomer by means of a sulfur group having a polythiosulfenamide function, of formula: ≡Si-A-Sx—NR1R2, (I) in which: A is a divalent bond group, whether straight-chain or branched, which makes it possible to join the polythiosulfenamide group to a silicon atom of the organosilicon compound; x is an integer or fractional number of from 2 to 4; R1 represents hydrogen or a monovalent hydrocarbon group; R2 represents a monovalent hydrocarbon group selected from among C3-C8 alkyls, whether straight-chain or branched, C5-C10 cycloalkyls, C6-C18 aryls and (C6-C18)aryl-(C1-C8)alkyls; R1 and R2 possibly forming together and with the nitrogen atom to which they are bonded a single hydrocarbon ring. Tires and tire treads comprising a composition of this type.
摘要翻译:可用于制造轮胎的弹性体组合物,至少基于(i)二烯弹性体,(ii)作为增强填料的无机填料和(iii)作为(无机填料/二烯弹性体)偶联剂的有机硅化合物, 至少是双官能的,并且可以通过具有式:Si-A-Sx-NR 1 R 2,(I)的具有聚亚硫酰胺官能团的硫基接枝到弹性体上,其中:A是 无论是直链还是支链的二价键基团,这使得可以将多亚硫酰胺基团连接到有机硅化合物的硅原子; x是2到4的整数或小数; R 1表示氢或一价烃基; R 2表示选自C 3 -C 8烷基,无论是直链还是支链,C5-C10环烷基,C6-C18芳基和(C6-C18)芳基 - (C1-C8)烷基的一价烃基; R 1和R 2可以一起形成,并与它们所键合的氮原子形成单个烃环。 包括这种类型的组合物的轮胎和轮胎胎面。
摘要:
Novel organosilicon compounds having a second order hyperpolarizability coefficient .beta. greater than zero, well suited for use in the field of nonlinear optics, e.g., in telecommunication devices, have the general formula: ##STR1## which n is an integer ranging from 1 to 20; R.sub.1 is an electron donating group; R.sub.2 is an electron accepting group; R.sub.3 is an alkyl radical having from 1 to 8 carbon atoms, a hydrogen atom, an aryl radical, or an R.sub.1 or R.sub.2 radical; and R.sub.4 is an alkyl radical having from 1 to 8 carbon atoms, a hydrogen atom, an aryl radical, or an R.sub.1 radical when R.sub.3 is not an R.sub.2 radical or an R.sub.2 radical when R.sub.3 is not an R.sub.1 radical.
摘要:
Boron/nitrogen/silicon preceramic polymers are prepared by copolymerizing at least one trihaloborane with at least one disilazane and at least one B-trichloroborazine; the resulting polymers, advantageously in fibrous form, are then facilely crosslinked and pyrolyzed into boron nitride ceramic materials.
摘要:
Highly pure boron nitride ceramic material, devoid of silicon values and having low carbon content, is prepared by pyrolyzing, under an atmosphere of ammonia, the product of the reaction between (i) at least one B-trihalogeno-borazole having the formula: ##STR1## and (ii) at least one primary amine having the formula:H.sub.2 N--Rin which formulae X is a halogen atom and R is an optionally substituted hydrocarbon radical having from 1 to 6 carbon atoms.
摘要:
Compounds of formula ##STR1## in which n denotes an integer from 1 to 10 and X and Y, which are identical or different, each denote an electron-attracting group, are made by reacting a halogenating agent with a compound of formula ##STR2## in which R, X and Y are as hereinbefore defined, anionized by a base.