Polyester thermo sets

Small amounts of TAIC together with DAP have been used to cure unsaturated polyesters in glass-reinforced thermo sets (131). It has been used with polyfunctional methacrylate esters in anaerobic adhesives (132). TAIC and vinyl acetate are copolymerized in aqueous suspension, and vinyl alcohol copolymer gels are made from the products (133). Electron cure of poly(ethylene terephthalate) moldings containing TAIC improves heat resistance and transparency (134). 

From the beginning, poly(ester-imide)s had been developed as thermo-setting polymers. In the 1970s a development was started to use imide modification for improving the properties of thermoplastic polyesters. Later on in the patent literature liquid crystalline polymers can be found as being claimed as molding resins. 

Thermo set polymers Alkyd resins Amino resins Epoxy resins Phenolic resins Poly(bis maleimide) Polyesters, unsaturated Thermoset resin Tohprene TOR Torelina Torlon TP 301 TPX... 

Type Poly- ethylene Chlorinated Rubber Chlorosul-fonated Chloro- Polyethy-prene lene Eluoro- carbon Urethane Vinyl Vinyl- Alkyd (Approx 1 1) Polyester Alkyd (Oil-free) Acrylic (Thermo- setting)... 

Thermo set polyesters are typical of the thermoset plastics—the characteristics of which are good temperature resistance, good tensile strength and stiffness, a high degree of hardness, low impact strength unmodified, low extensibility, and generally superior resistance to creep and cold flow. Properties of some typical materials are shown in Table 1-4. 

The synthesis of unsaturated polyesters has been studied by several workers. Such materials have been used in the formation of cross-linked resins, particularly where reinforced polymers are to be used. The kinetics of the thermo-setting process has been investigated by differential scanning calorimetry. Photocrosslinkable unsaturated polyesters containing pendant chalconyl and cinnamylidenemalomyl moieties have also been produced. Such polymers were found not to exhibit any pronounced photofastness. Several other studies have described the synthesis and characterization both of the prepolymer, and the unsaturated resin. ... 

All kinds of sheet or board material could be used as stiffener materials for the flexible circuits however, several materials are conunouly used.Typical stiffener materials for the traditional flexible circuits are listed in Table 61.19. Paper phenol boards and glass-epoxy boards are employed for relatively thick requirements. Polyimide films and polyester films are employed for relatively thin requirements. Aluminum plates and stainless steel plates are commonly used as the Stiffener materials of flexible circuits. A specialty of the metal stiffeners is their forming capabilities after they are bonded on flexible circuits. Paper phenol and polyester are not available for thermo setting adhesives because of the low heat resistance. 

Dr. Isao Noda has been working on the family of PHA called Nodax that consists of f/ j-3-hydroxyalkanoate comonomer units with medium size chain side groups and j-3-hydroxybutyrate. Because of the unique design of their molecular structure, the Nodax class PHA copolymers have a set of useful attributes, including polyolefin-like thermo-mechanical properties, polyester-like physicochemical properties, and interesting biological properties. Therefore, a broad range of industrial and consumer product applications are anticipated. 

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