Reaction of Hydroxyl Terminated Polydimethylsiloxane with Epoxy Resin
May 22, 2023
The copolymer can be cured at 14o ℃, 1h, 18 ° C, and 2h. The long carbon chain Cu at both ends of PDMS can increase its compatibility with bisphenol A, thereby increasing cohesion. Add 10% PDMS with a molecular weight of 3000 to disperse the soft chain segments into epoxy resin, and the minimum particle size can reach 0 23 µ m., toughness improved.
Reaction between Vinyl Silicone and Vinyl Epoxy Resin
An epoxy resin containing vinyl in its molecular structure was prepared by the reaction of o-cresol linear phenolic epoxy resin with methacrylic acid. Then, 2-ethyl-tert-butylperoxyhexanoic acid and 1,1-2- (tert-butylperoxide) -3,3,5-trimethylhexanoic acid were used as initiators for free radical polymerization with vinyl PDMS to obtain modified epoxy resin samples VSl, VS2, VS3, VS4, VS5, VS6. Among them, samples VSl~VS5 have vinyl at the end group position; Sample VS6, with vinyl at the side group position.
A vinyl siloxane modified cresol linear phenolic epoxy resin was synthesized using a similar method, and a cresol linear curing agent was also synthesized. The siloxane modified system obtained after curing has lower elastic modulus and higher elongation at break compared to the system without siloxane modification. Modified resins can solve the problem of "popcorn explosion" when used as electronic packaging materials.
Preparation of Organosilicon Modified Epoxy Resin by Dispersion Polymerization
Dispersion polymerization is the process of obtaining insoluble polymer particles from soluble monomers through the stabilizing effect of stabilizers. This polymerization process usually results in polymer microspheres of a certain size. Due to the action of surface polymer dispersants, the microspheres automatically separate and exist stably.
A multifunctional group coupling agent was used to synthesize a uniformly dispersed modified o-cresol epoxy resin with light silicone oil through dispersion polymerization. The silicon burning coupling agent hydrolyzes to produce silanol groups, which condense with light end group silicone oil to form surface terminated amino polysiloxane particles. Under the action of the dispersant, the particles can be stably dispersed in organic solvents. Adding epoxy resin, vigorously stirring and refluxing reaction were carried out to remove the solvent, resulting in a modified epoxy resin with controllable particle size of organic silicon dispersed phase. The internal stress was significantly reduced.
Other copolymerization modifications
In terms of modifying epoxy with organic silicon, the organic silicon used is generally a macromolecular system, and the organic silicon chain segments are introduced through the reaction of active end groups such as tibia and amino groups carried by the organic silicon chain end with the epoxy group. However, this not only consumes the epoxy group, but also reduces the cross-linking degree of the curing network, and the introduction of molecular flexible chain segments correspondingly reduces the rigidity of the system, Therefore, toughening is accompanied by a decrease in heat resistance (stone).
Our main products are Acrylic Modified Silicone Resin Emulsion，Epoxy Modified Silicone Resin Emulsion，Smokeless Silicone Resin，Self-drying Silicone Resin，Highly Active Silicone Resin，Methyl Silicone Resin Intermediate.
