SURFACING FILM FOR COMPOSITE STRUCTURES AND METHOD OF MAKING SAME Russian patent published in 2017 - IPC C09D163/00 C08J5/22 C08L63/00 C08L81/06 C08L21/00 

FIELD: chemistry.

SUBSTANCE: invention relates to surface films of composites, in particular, to surface films for reinforced polymer matrix composite structures, method for preparing them. Surface film is formed from a curable composition based on a resin, containing epoxy-novolac resin, having epoxy functionality greater than one and having certain structure, tri-functional or tetra-functional epoxy resin, ceramic microspheres, latent amine-based curing agent, inorganic filler particles and reinforcing agent. Filler is selected from a group, consisting of talc, mica, calcium carbonate, aluminium oxide and pyrogenic silica. Curing agent is an adduct obtained beforehand, formed by reacting diglycidyl ether of tetrabromobisphenol A; bisphenol A and an elastomer. Surface film has high T_c and high cross-link density after hardening, as well as high resistance to solutions for removing lacquer coating. Surface film can optionally contain electroconductive additives, to ensure sufficient conductivity for lightning strike protection (LSP) or electromagnetic interference (EMI) shielding. Invention also relates to a composite structure, including a composite substrate, having said surface film formed thereon. Said composite substrate includes, for example, a prepreg layup, which consists of a set of prepreg layers, laid one over other.

EFFECT: each layer contains reinforcing fibers impregnated with polymer binder.

14 cl, 1 dwg, 4 tbl