프리프레그 및 섬유 강화 복합 재료

• Main Authors: SANO KENTARO, KURODA TAIKI, UCHIDA HIROYUKI, KAMAE TOSHIYA
• Format: Patent
• Language: Korean
• Published: 22.07.2020
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

[A] 에폭시 수지 및 [B] 경화제로서 방향족 우레아를 포함하는 에폭시 수지 조성물과 강화 섬유로 이루어지는 프리프레그로서, 에폭시 수지 조성물이 하기 조건(a)~(e)를 만족하는 프리프레그: (a) : [A] 에폭시 수지로서 페놀노볼락형 에폭시 수지를, 전 에폭시 수지 100질량부 중 50~100질량부 포함하고, 또한 그 반복단위 n이 n≥2인 성분을, 전 에폭시 수지 100질량부 중 50~80질량부 포함하고, (b) : 전 에폭시 수지의 평균 에폭시 당량이 165~265g/eq이고, (c) : 에폭시 수지 조성물을 85℃·95% RH 분위기 하에서 2시간 보관한 경우의 흡수율이 조성물의 3.0질량%이하이고, (d) [B] 경화제로서 실질적으로 방향족 우레아만을 포함하고, (e) 실질적으로 디시안디아미드를 포함하지 않는다. Disclosed is a prepreg comprising an epoxy resin composition containing [A] an epoxy resin and [B] a curing agent, and a reinforcing fiber, wherein the epoxy resin composition satisfies the following conditions (a) to (e): (a) [A1] an epoxy resin represented by the general formula (I) is contained as the epoxy resin [A] in an amount of 50 to 100 parts by mass in 100 parts by mass of the entire epoxy resin, and [A1'] an epoxy resin satisfying an inequality: n ≥ 2 among the component [A1] is contained in an amount of 50 to 80 parts by mass in 100 parts by mass of the entire epoxy resin;wherein, in the general formula (I), R1, R2and R3each independently represent a hydrogen atom or a methyl group, and n represents an integer of 1 or more; (b) the entire epoxy resin has an average epoxy equivalent of 165 to 265 g/eq; (c) a water absorption coefficient as determined when the epoxy resin composition is stored in an atmosphere at 85°C and 95%RH for 2 hours is 3.0% by mass or less based on 100% by mass of the epoxy resin composition; (d) [B1] an aromatic urea is contained as [B] a curing agent; and (e) the content of [B2] dicyandiamide of the curing agent [B] is 0.5 part by mass or less based on 100 parts by mass of the entire epoxy resin. The present invention provides a prepreg which achieves both high heat resistance and low color and does not cause white spots on the surface of a molded article, and is capable of obtaining a fiber-reinforced composite material having excellent appearance and is also capable of obtaining a fiber-reinforced composite material having high heat resistance even when curing is performed under the condition where moisture can be mixed therein.