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In materials science, a thermosetting polymer, often called a thermoset, is a polymer that is obtained by irreversibly hardening ("curing") a soft solid or viscous liquid prepolymer . [1] Curing is induced by heat or suitable radiation and may be promoted by high pressure or mixing with a catalyst .
A thermoset polymer matrix is a synthetic polymer reinforcement where polymers act as binder or matrix to secure in place incorporated particulates, fibres or other reinforcements. They were first developed for structural applications, [ 1 ] such as glass-reinforced plastic radar domes on aircraft and graphite - epoxy payload bay doors on the ...
The mixture is then sonicated and mixed until the nanotubes are evenly dispersed, then cast. While this method is widely used, the sonication can damage the carbon nanotubes, the polymer must be soluble in the solvent of choice, and the rate of evaporation can often lead to undesirable structures like nanotube bundling or polymer voids.
Thermosets, or thermosetting polymers, can melt and take shape only once: after they have solidified, they stay solid and retain their shape permanently. [16] If reheated, thermosets decompose rather than melt. Examples of thermosets include epoxy resin, polyimide, and Bakelite. The vulcanization of rubber is an example of this process.
The generalised chemical structure of polyisocyanurate showing the isocyanurate group. The polyols are abbreviated as R-groups.. Polyisocyanurate (/ ˌ p ɒ l ɪ ˌ aɪ s oʊ s aɪ ˈ æ nj ʊər eɪ t /), also referred to as PIR, polyol, or ISO, is a thermoset plastic [1] typically produced as a foam and used as rigid thermal insulation.
In thermoset polymers (thermosetting plastic), disulfide bridges and other covalent cross links give rise to a hard structure which can withstand very high temperatures. These cross-links are particularly helpful in improving tensile strength of materials which contain much free volume prone to crazing, typically glassy brittle polymers. [ 8 ]
An acrylic resin is a thermoplastic or thermosetting plastic substance typically derived from acrylic acid, methacrylic acid and acrylate monomers such as butyl acrylate and methacrylate monomers such as methyl methacrylate. Thermoplastic acrylics designate a group of acrylic resins typically containing both a high molecular weight and a high ...
Historically, thermoset polymer systems that were processable by virtue of topology changes within the covalent networks as mediated by bond exchange reactions were also developed by James Economy’s group at UIUC in the 1990s [4] [5] including consolidation of thermoset composite laminae. [9]