MQ Silicone Resin of Silicone Resin Series
Organic silicone materials have the properties of both organic and inorganic materials, showing many unique physical and chemical properties, such as non-toxic, odorless, weatherproof, electrical insulation, oxidation resistance, low surface energy, biological inertia, flame retardant, hydrophobicity, etc. It has been widely used in national defense, energy development, light industrial food, textiles, etc. Electronic, electrical, mechanical, construction, transportation, medical, daily life and other fields. At present, the core products of silicone industry are silicone rubber, silicone oil, silane coupling agent and silicone resin. MQ silicone resin is one of the organosilicon resins. It has unique structure and excellent performance. It is mainly used as surface treatment agent and tackifier of organosilicon pressure sensitive adhesive, reinforcing filler of silicone rubber, organosilicon defoamer, anti-sticking agent, high temperature resistant coating, demoulding agent, etc.
1. Structure and Classification of MQ Resin
MQ silicone resin is a kind of organosilicon resin with unique structure. It is a three-dimensional spherical silicone resin produced by the co-hydrolysis-condensation reaction of organosilicon compounds containing four-functionality siloxane chains (SiO4/2, Q) and organosilicon compounds containing single-functionality siloxane chains (R3SiO1/2, M). Its molar mass is generally 1000-8000g/mol. It has a state from viscous fluid to solid powder. It is hard and brittle, and its glass transition temperature (Tg) range is wide.
It is generally believed that MQ silicone resin is a double-layer compact sphere, in which the spherical core is a cage-like Si O 2 with Si-O chain connection, high density and degree of polymerization 15-50, and the spherical shell is a R3SiO 1/2 layer with low density.
MQ silicone resin has many different types due to the different organic group R on the spherical shell.
When R is all methyl, it is called methyl MQ silicone resin or MQ silicone resin for short; when part R is H, it is called methyl MQ silicone resin; there are also methyl phenyl MQ silicone resin, vinyl MQ silicone tree, phenyl MQ silicone resin, fluorine MQ silicone resin, MDQ, MTQ silicone resin, etc. The properties and applications of MQ silicone resin mainly depend on the synthetic conditions and the types and quantities of organic groups in the molecule, i.e. the ratio of the number of M and Q chains; the organic group R mainly increases the compatibility with other components, and the SiO4/2 chains mainly enhance the strength of composites.
From Silicone Public