What are the main raw materials for hand lay-up molded fiberglass?

① Fiberglass products: There are many types of fiberglass products. Commonly used in industry include untwisted roving, twisted yarn, chopped strand mat, surface mat, nonwoven fabric, unidirectional fabric, plain weave fabric, twill weave fabric, untwisted roving checkered fabric, and satin fabric. Currently, the fiberglass products used in automotive parts mainly include: surface mat, chopped strand mat, and untwisted roving checkered fabric (referred to as "checkered fabric").

② Resin: Originally, resin referred to the lipid-like substance extracted from tree secretions. Later, after the artificial synthesis of resins became possible, the term "resin" came to refer to all artificially synthesized liquid polymer compounds. There are many types of resins, but the most commonly used resin for hand lay-up fiberglass is unsaturated polyester resin;

③ Curing agents and accelerators: Three common curing agents for polyester resin are cyclohexanone peroxide (white paste), methyl ethyl ketone peroxide (colorless transparent liquid), and benzoyl peroxide (white solid or paste). During use, the curing agent only releases free radicals and cures the resin when heated or under the action of an accelerator;

④ Fillers: Fillers are added to fiberglass to improve certain properties or reduce costs, and are themselves relatively inert. Fillers are not essential materials in fiberglass products and are usually unnecessary;

⑤ Accelerators: Two common accelerators are cobalt naphthenate (purple-blue liquid) and dimethylaniline (pale yellow transparent liquid). In practice, the accelerator is usually added to a large container of resin to prepare a "bulk mix." When applying the fiberglass coating, measure the resin from the "bulk materials" according to the construction needs, and finally add the hardener;

⑥ Pigment paste: Pigment paste is also a type of resin, equivalent to a dye. Add the corresponding color pigment paste to the gel coat resin according to the product's color requirements and mix thoroughly. The amount of pigment paste added is generally 1% to 4% of the resin weight;

⑦ Other additives, such as diluents, light stabilizers, flame retardants, etc.