摘要:
A process for preparing organosiloxane block copolymers which comprises reacting (a) an organopolysiloxane containing Si-bonded hydroxyl groups and having an average molecular weight of at least 800 g/mole, in which at least 80 mole percent of the units are siloxane units, and one valence of each silicon atom is satisfied by an SiC-bonded organic radical, while the remaining silicon valences are satisfied by siloxane oxygen atoms or hydroxyl groups, with (b) a diorganopolysiloxane having one Si-bonded hydroxyl group in each terminal unit and an average of at least 10 silicon atoms per molecule in the presence of (c) an organic solvent and (d) an alkali metal carbonate and/or an alkali metal carboxylate to form an organosiloxane block copolymer.
摘要:
Organopolysiloxane modified organic polymers are prepared by reacting organic polymers containing C-bonded hydroxyl groups with organopolysiloxanes containing Si-bonded hydroxyl groups and/or alkyl groups which are bonded to silicon via oxygen in the presence of water in excess of any formed during the reaction.
摘要:
In the preparation of microcapsules having shell walls of organopolysiloxane and a core material, the shell walls are produced in situ by hydrolysis and polycondensation of organosilanes and/or their condensates having not more than 4 silicon atoms.
摘要:
The invention relates to organopolysiloxanes with dye residues comprising units of the general formula R1a(RO)bAcR2dSiO(4−a−b−c−d)/2 (I) wherein R can be identical or different and is hydrogen atom or monovalent, substituted or unsubstituted hydrocarbon radical, R1 can be identical or different and is hydrogen atom or monovalent, SC-bonded hydrocarbon radical, R2 can be identical or different and is substituted, monovalent, Si—C bonded hydrocarbon radical, A can be identical or different and is a radical of a water-soluble organic dye containing at least one of sulfonic acid groups, sulfonate groups, or metal complexes thereof, a is 0, 1, 2, or 3, b is 0, 1, 2 or 3, d is 0, 1, 2, or 3 and c is 0, 1 or 2 with the proviso that the sum of a, b, c and d is less than or equal to 3, the organopolysiloxanes have at least one radical, and, in the units of the formula (I) where c is other than 0, d is 0.
摘要:
A novel process for preparing organosilicon compounds containing (meth)acxyloxy groups is described, in which alkoxylated alk-2-yne 1,4-di(meth)acrylates (1) of the formula ##STR1## where R.sup.2 is a hydrogen atom or a methyl radical,R.sup.3 is a linear or branched alkylene radical having from 1 to 6 carbon atoms per radical andR.sub.4 is a linear or branched alkylene radical having from 1 to 6 carbon atoms per radical, andz is an integer from 1 to 12,are reacted with organosilicon compounds (2) comprising units of the formula ##STR2## where R is an identical or different monovalent, optionally halogenated hydrocarbon radical having from 1 to 18 carbon atoms per radical, ande is 0 or 1, on average from 0.01 to 1.0,f is 0, 1, 2 or 3, on average from 0.0 to 3.0, andhaving at least one Si-bonded hydrogen atom per molecule in the presence of catalysts (3) which promote the addition Si-bonded hydrogen onto aliphatic multiple bonds and also in the presence of polymerization inhibitors (4), where alkoxylated alk-2-yne 1,4-di(meth)acrylates (1) are used in amounts of from 1.01 to 1.5 mole per gram atom of Si-bonded hydrogen in organosilicon compound (2).
摘要:
The organopolysiloxane particles consist of a single molecule, are crosslinked and have an average diameter of 5 to 200 nm. At least 80% of the particles have a diameter which deviates from the average diameter by not more than 30%. The particles are soluble in a solvent to the extent of at least 5% by weight.
摘要:
An epoxy resin molding material comprising an epoxy resin, a phenolic resin and a powder flexibilizer which has a core-shell structure composed of a solid silicone core and an organic polymer shell is a reliable epoxy resin molding material for sealing electronic parts which is excellent in, for example, thermal shock resistance and reflow soldering resistance, and is free from the troublesome deterioration in, for example, the appearance and marking properties of molded products, and to provide a semiconductor sealed by the molding material.
摘要:
The invention relates to partially crosslinked organopolysiloxanes which contain a radical forming group, a base-catalyzed process for their preparation, graft copolymers produced from these organopolysiloxanes and a process for the preparation of the graft copolymers. The present invention avoids problems related to known methods wherein a considerable portion of the organopolymer chains do not graft to the organopolysiloxane graft back-bone but remain as an unattached homopolymers.
摘要:
Transition metal-containing organosiloxanes of at least three organosiloxane units, comprising at least one transition metal complex, chemically bonded via ligands selected from among amino, phosphino or sulfido groups of Pt, Pd, Rh, Ru, Os or Ir, excluding those organosiloxanes which contain exclusively Pt(O) complexes bonded via amino ligands, are used as homogeneous hydrosilylation catalysts.
摘要:
The invention relates to a process by which organosilicon compounds carrying sulfur-containing organic radicals can easily be prepared by reacting organosilicons of the general formulaR.sub.a (R.sup.1 O).sub.b R.sup.2.sub.c SiO.sub.(4-a-b-c)/2(I)in whichR can be identical or different and is a monovalent organic radical,R.sup.1 can be identical or different and is a hydrogen atom or a monovalent organic radical,R.sup.2 can be identical or different and is a radical --QX, where Q is a divalent hydrocarbon radical and X is a halogen atom,a is 0, 1, 2 or 3,b is 0, 1, 2 or 3 andc is 0, 1, 2 or 3,with the proviso that the organosilicon compound has at least one radical R.sup.2 per molecule and the sum of a, b and c is less than or equal to 4, with sulfite in the presence of water.