AB crosslinked polymers based on cationomeric polyurethane and poly(methyl methacrylate): Static and dynamic mechanical studies

Abstract

ABSTRACT:Vinyl-terminated polyurethane (VTPU) was prepared by end-functionalizing isocyanate-terminated prepolymers with 2-bromoethanol and subsequently quartenizing with 4-vinylpyridine. The vinyl functionality was then effectively utilized for preparing AB crosslinked polymers (ABCPs) with methyl methacrylate (MMA). ABCPs prepared with variable weight ratios on PTMG 1000 -based VTPU/MMA (8/2, 6/4, 5/5, 4/6, 2/8) and those prepared at a 5/5 weight ratio with different polyols (PTMG 1000 , PPG 1000 , and PCL 1250 ) in VTPU were characterized by Fourier transform infrared spectroscopy (FTIR) and further analyzed for thermal and mechanical properties. FTIR spectral results confirm quartenization of heterocyclic nitrogen, leading to crosslinking. Thermogravimetric analyses show enhanced thermal stability of the crosslinked systems. The stress-strain measurements reveal increasing tensile strength with increasing amounts of MMA. Comparison of dynamic mechanical spectra of ABCPs based on PTMG 1000 shows that the 5/5 composition exhibits good damping over a broad temperature range.

Novel AB crosslinked polymer networks based on 1‐vinylimidazole‐ terminated polyurethane and poly(methyl methacrylate)

“…The T g of PU increases at the same time as the T g of PMMA decreases. This kind of shift in T g is called inward shift 7. This is in good agreement with data available in the literature12 and it indicates strong interlocking between PU and PMMA chains.…”

“…Despite the higher crystallinity of PCL compared to PTMG, the tensile strength of PCL‐based ABCP is lower. This may be due to disorientation of the polymer chains, where crystallites can act as stress concentrators and thereby weaken the crosslinked polymer 7, 21…”

“…The term AB crosslinked polymer (ABCP) refers to a polymer network where polymer A is bonded to polymer B at both ends and various points along the chains 1–9. Here, polymer A is bonded primarily to polymer B and is not crosslinked to itself.…”

“…end‐functional polyurethane ionomers, would be of great interest. In continuation of our efforts on the synthesis of novel ABCPs, end‐functional 4‐vinylpyridine telechelic polyurethane16 was successfully synthesized and used to prepare ABCPs 7. In this paper, for the first time, the synthesis of 1‐vinylimidazole telechelic polyurethane containing quaternized nitrogen atoms is reported.…”

Novel high‐performance wave‐transparent aluminum phosphate/cyanate ester composites

“…Similar phenomena also appear in other polymers and polymeric composites. [25][26][27][28] When a composite has very small content of AlPO 4 (KH-550) (up to 5 wt %), its two T g values are similar with the single T g value of CE resin; while when a composite has somewhat large content of AlPO 4 (KH-550), its two T g values tend to shift toward lower temperature range. The phenomenon can be mainly interpreted by two facts that the addition of AlPO 4 (KH-550) to CE resin changes the curing reaction and thus the cured structure.…”