摘要:
Aminoalkyl-functional siloxanes are prepared efficiently by a continuous process in which a cyclic silazane and a hydroxyl-functional siloxane are fed continuously to a reaction zone, reacted in the reaction zone, and the aminoalkyl product and any unreacted starting materials are removed from the reaction zone. The process is effective even with hydroxyl-functional siloxanes having a very low weight percentage of hydroxyl groups.
摘要:
A water-soluble mixed ether of .alpha.-, .beta.- or .gamma.-cyclodextrin having at least one lipophilic and one hydrophilic radical per cyclodextrin molecule, of the following formula I: ##STR1## where R is hydrogen or R1 or R2 andR1 is a hydrophilic radical andR2 is a lipophilic radical andthe MS for R1 is 0.3 to 2.0 andthe MS for R2 is 0.2 to 1.0 andn is 6, 7, or 8.
摘要:
A method for the solvent-free, continuous production of organopolysiloxane/polyurea/polyurethane block copolymers involves reacting amino-functional siloxanes with polyisocyanates and organic polyhydroxy compounds. The organopolysiloxane/polyurea/polyurethane block copolymers produced by means of the inventive method are useful for numerous purposes, for example as elastomers, caulks, sealants, and films.
摘要:
Addition polymers prepared in the presence of condensation-crosslinkable silyl-functional RAFT reagents are preparable in solid or liquid form with low polydispersion.
摘要:
Oligomers are prepared by polymerizing unsaturated silanes, optionally along with a copolymerizable ethylenically unsaturated monomer. The oligomers are particularly useful for preparing core-shell particles.
摘要:
Organopolysiloxane/polyurea/polyurethane block copolymer elastomers exhibiting improved physical properties are prepared by reacting diisocyanates with aminoalkyl-functional organopolysiloxanes containing substantially no cyclic siloxanes, prepared by reacting a cyclic silazane with a bis(hydroxy)-organopolysiloxane. Traditional hydroxyl and amino-functional chain extenders may be reacted as well, to produce a wide range of block copolymer elastomers.
摘要:
Ultrahydrophobic coatings are prepared by coating a substrate with a coating system containing an addition polymer containing moieties derived from a mono- or polyethylenically unsaturated organopolysiloxane, and hydrophillic particles.
摘要:
Organopolysiloxane/polyurea/polyurethane block copolymers of general formula (1) B—{[NR4—CR2—SiR2—(O—SiR2)n—CR22—NR4—CO—NH—Y—NH—CO]a-[Z-D-Z-CO—NH—Y—NH—CO]b—[NR4—CR22—SiR2—(O—SiR2)n—CR22—NR4—CO—NH—Y—NH—CO—NH—Y—NH—CO]e}d—B, are obtained by reacting aminomethyl terminal polydimethyl siloxanes with diisocyanates and optional chain extenders, have low softening temperatures and reduced color.