Requirements, matrix resins properties

Cured Bisbenzocyclobutene (BCB) terminated resin systems exhibit good mechanical properties with 70Z to 85X retention of properties at 260 C and high thermal stability. The Materials Laboratory has studied these materials for use as high temperature structural matrix resins in composites. They are well suited for this use since they do not require the use of catalysts and cure without the evolution of volatiles. 

Throughout this chapter the chemical concepts employed to synthesize and cure addition poly(imides) have been discussed and their use as matrix resins for fiber composites has frequently been mentioned. The most important property of the imide backbone structure is the inherent thermal stability. The target of achieving the temperature performance of linear poly(imide) has not been reached, because of the aliphatic nature of the reactive endgroups, and because of the low molecular weight of the imide backbone required for processing. Future developments of addition polyimides will, as in the past, focus on the requirement of high thermal and thermal oxidative stability of the crosslinked... 

Hand lay-up - [REINFORCED PLASTICS] (Vol 21) -composite fabrication [COMPOSITEMATERIALS - SURVEY] (Vol 7) -resin properties required for [COMPOSITEMATERIALS - POLYMER-MATRIX - THERMOSETS] (Vol 7)... 

Polymers are being more frequently placed in structural roles as, e.g., matrix resin in particulate and fiber-reinforced composites and adhesives. This places requirements on polymers that heretofore have received little attention. One important property required of structural materials is resistance to fracture. 

The matrix resin should have excellent comprehensive properties, including mechanical, electrical, thermal performance, chemical resistance, anti-aging, flame retardancy and so on. However, it is impossible for an Individual matrix resin to have all the properties simultaneously, so the appropriate one should be chosen according to usage requirements and characteristics of packing materials. For example, fire retardancy, compatibility of filler and matrix resin, and dispersibility of filler in the resin should be taken into account to make the filled composite material meet usage requirements. 

Zisman emphasized the requirement that the resin must wet the reinforcement to achieve the desired adhesion. He described the requirements of wetting as the surface tension of the matrix resin being less than the surface energy of the reinforcement. These conditions would appear to be met by the use of most thermosetting matrix resins and untreated reinforcement (heat cleaned fiberglass), yet these combinations produce composites with lower mechanical properties, both dry and wet, than produced with silane treated reinforcement. A probable explanation is that the presence of water on the surface of the untreated reinforcement interferes with or prevents complete wetting of the reinforcement by the matrix resin. 

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