POLYMERIC MATRIX MATERIALS 91 Table 4.4 Approximate Properties of Selected Polymer Matrix Materials Ts (C) Matrix Material GIc Details (J/m2) E(GPa) e(%)】 Dry Wet~ 920 541 3.8 8.4 107 85 Hexcel RTM6 168 2.9 3.4 183 167 Resin transfer molding resin F584 175 4.1 1.8 171 121 First generation pre-preg epoxy 914 103 3.9 1.5 190 N/A First generation pre-preg epoxy F593 420 3.0 172 131 Pre-preg epoxy 977-3 217 N/A N/A 218 178 Pre-preg epoxy 977-2 478 3.5 N/A 212 N/A Toughened version of 977-3 6376 432 3.0 3.1 N/ N/A Toughened A pre-preg epoxy 8552 N/A 4.0 4 195 154 Toughened pre-preg epoxy 524C 67 3.3 2.9 220 Modified BMI resin PMR 15 Polyimide 280 4.0 1.1 340 Udel 3200 2.7 50 190 Polysulfone Radel 5500 2.8 60 220 Polyarylsulfone PES 2600 2.9 40 220 Polyether sulfone Ultem 3700 4.0 60 220 Polyetherimide Torlon 3400 4.9 15 275 Polyamideimide PEEK 4400 3.6 30 145 Polyetheretherketone
POLYMERIC MATRIX MATERIALS 91 Table 4.4 Approximate Properties of Selected Polymer Matrix Materials Matrix Material Details alc (J/m 2) E (GPa) e (%) Tg (°C) Dry Wet 920 541 3.8 8.4 107 Hexcel RTM6 168 2.9 3.4 183 Resin transfer molding resin F584 175 4.1 1.8 171 First generation pre-preg epoxy 914 103 3.9 1.5 190 First generation pre-preg epoxy F593 420 3.0 2 172 Pre-preg epoxy 977-3 217 N/A N/A 218 Pre-preg epoxy 977-2 478 3.5 N/A 212 Toughened version of 977-3 6376 432 3.0 3.1 N/ Toughened A pre-preg epoxy 8552 N/A 4.0 4 195 Toughened pre-preg epoxy 524C 67 3.3 2.9 220 Modified BMI resin PMR 15 Polyimide 280 4.0 1.1 340 Udel 3200 2.7 50 190 Polysulfone Radel 5500 2.8 60 220 Polyarylsulfone PES 2600 2.9 40 220 Polyether sulfone Ultem 3700 4.0 60 220 Polyetherimide Torlon 3400 4.9 15 275 Polyamideimide PEEK 4400 3.6 30 145 Polyetheretherketone 85 167 121 N/A 131 178 N/A N/A 154
92 COMPOSITE MATERIALS FOR AIRCRAFT STRUCTURES waeho8iemo8oeo ● CH2-CH-CH2 H2C CH CH2-NCH2NCH2-CH-CH2 H2C-CH CH2 D】 wooO0-c H2C-CH-CH2 H2C CH-CH2-O-CH2-CH2-CH2-CH2-O-CH2-CH-CH2 d) Fig.4.6 Major epoxy resins used in aerospace composite matrices:a)bisphenol A- epichorohydrin DGEBA)resins;b)tetraglycidyl derivative of diamino diphenyl methane (TGGM);c)triglycidyl derivative of p-aminophenol (TGAP);d)reactive diluent epoxy resin such as the bis epoxy from butane diol. characteristics of epoxy formulations before cure.This does,however,result in some loss in final high-temperature properties. 4.3.1.1 Curing of Epoxy Resins.The epoxide group has unfavorable bond- ing angles,which makes it chemically reactive with a variety of substances that can easily open the ring to form a highly cross-linked structure.The cross linking may occur through the epoxy groups or the resulting hydroxy groups. While epoxy resins can be self-polymerized using suitable catalysts,the majority of applications make use of curing agents-often called hardeners.The major classes of curing agents include aliphatic amines,which give cold-curing systems and aromatic amines and polyanhydrides,which give heat-curing
92 COMPOSITE MATERIALS FOR AIRCRAFT STRUCTURES O r CH,~ OH "t CH^ O H2C-CH-H 2 H2-CH-CH H2-CH-CH 2 a) H2C'-CH"-CH2 ~ CH2-CH'-CH2 CH2._.CH_CH 2 \o' b) H2C-CH~H2~ N-C%-O-CHz-CH-CH2 H2C_CH~H2 j ~--~ \O / c) H2C-CH---CH2-O--CH2-CH2-CH2-CH2-O-CH2-CH-CH2 d) Fig. 4.6 Major epoxy resins used in aerospace composite matrices: a) bisphenol Aepichorohydrin (DGEBA) resins; b) tetraglycidyl derivative of diamino diphenyl methane (TGGM); c) triglycidyl derivative of p-aminophenol (TGAP); d) reactive diluent epoxy resin such as the bis epoxy from butane diol. characteristics of epoxy formulations before cure. This does, however, result in some loss in final high-temperature properties. 4.3.1.1 Curing of Epoxy Resins. The epoxide group has unfavorable bonding angles, which makes it chemically reactive with a variety of substances that can easily open the ring to form a highly cross-linked structure. The cross linking may occur through the epoxy groups or the resulting hydroxy groups. While epoxy resins can be self-polymefized using suitable catalysts, the majority of applications make use of curing agents---often called hardeners. The major classes of curing agents include aliphatic amines, which give cold-curing systems and aromatic amines and polyanhydrides, which give heat-curing