Synthesis and characterization of new functional poly(urethane‐imide) crosslinked networks

Abstract

ABSTRACT:To synthesize new functional poly(urethaneimide) crosslinked networks, soluble polyimide from 2,2Ј-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 4,4Ј-oxydianiline, and maleic anhydride and polyurethane prepolymer from polycaprolactone diol, tolylene 2,4-diisocyanate and hydroxyl ethyl acrylate were prepared. Poly-(urethane-imide) thin films were finally prepared by the reaction between maleimide end-capped soluble polyimide (PI) and acrylate end-capped polyurethane (PU). The effect of polyurethane content on dielectric constant, residual stress, morphology, thermal property, and mechanical property was studied by FTIR, prism coupler, Thin Film Stress Analyzer (TFSA), XRD, TGA, DMTA, and Nano-indentation. Dielectric constant of poly(urethane-imide) thin films (2.39 -2.45) was lower than that of pure polyimide (2.46). Especially, poly(urethane-imide) thin films with 50% of PU showed lower dielectric constant than other poly(urethaneimide) thin films did. Lower residual stress and slope in cooling curve were achieved in higher PU content. Compared to typical polyurethane, poly(urethane-imide) thin films exhibited better thermal stability due to the presence of the imide groups. The glass transition temperature, modulus, and hardness decreased with increase in the flexible PU content even though elongation and thermal expansion coefficient increased. Finally, poly(urethane-imide) thin films with low residual stress and dielectric constant, which are strongly affected by the morphological structure, chain mobility, and modulus, can be suggested to apply for electronic devices by variation of PU.

Bulk Preparation of Radiation Crosslinking Poly (Urethane-Imide)

“…Therefore, the preparation of radiation crosslinking poly(urethane-imide), the same need to import some unsaturated group into its molecular backbone (soft segment or hard segment ) or its chain end, to enhance adiation crosslinking effect. In fact, so far, although preparation research of poly(urethane-imide) made a lot of progress [49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67], but report closely related with radiation polymerization also not too much. Of course, we can prepare radiation crosslinking poly(urethane-imide) by using introduction of unsaturated bond into its molecular structure, especially hard segment structure, also through double end capping to prepare the radiation crosslinking poly(urethane-imide).…”

Synthesis and characterization of novel heat resistance poly(amide‐imide)s from N,N′‐[2,5‐bis(4‐aminobenzylidene) cyclopentanone] bistrimellitimide acid and various aromatic diamines

“…Therefore, preparation of soluble polyimides without perceptible loss of favorable properties has been a major research interest, and a great deal of efforts has been made to improve the processing characteristics of this class of polymers. One of the successful approaches to improve solubility is the incorporation of other functional groups such as amide,4–11 ester,12, 13 urethane,14, 15 and urea16, 17 linkages along the polymer skeleton.…”

Synthesis and characterization of novel thermoplastic poly(oligophosphazene‐urethane)s

“…One of the accepted approaches is chemical modification of the structure by copolymerization with thermally stable polymers. Recently, much attention has been paid to chemical modification with heterocyclic structures like imide, oxazolidone or triazine 6–11. Cyclophosphazene (CPZ) is an important class of organic–inorganic heterocyclic material.…”