Improved Resilience and Uniformity in Polysulfone Blends from an Accelerated Grafting Ring-Opening Polymerization Reaction with Benzoxazine

Abstract

BPA-based benzoxazine monomer (BA-a) solubilized in end-group ditosylated poly(ether sulfone) [α,ω-PSU(OTs) 2 ] undergoes an accelerated grafting ring-opening polymerization (ROP) to afford unique graft copolymer hybrids with predictable thermal properties and improved uniformity and superior mechanical properties. The α,ω-PSU(OTs) 2 was synthesized from the parent α,ω-dihydroxy poly(ether sulfone) with the conversion of end-groups quantified by 1 H NMR and GPC. The two polymers were used to create two blend series with a BPA-based benzoxazine monomer (BA-a) and heated to the polybenzoxazine-based products. The grafting ROP reaction of tosylated poly(ether sulfone) with the resulting polybenzoxazine network was studied by using DSC, FT-IR, SEM, and UV−vis and indicated that tosylated end-groups accelerate BA-a polymerization and afford products that are composed of P(BA-a)-graft-PSU with excess but well-mixed PSU. The approach allows for the fabrication of free-standing films that had higher tensile modulus, greater resiliency, and less mechanical property variation compared to their α,ω-dihydroxy poly(ether sulfone) analogues. The properties of the tosylated poly(ether sulfone) blend films and the accelerated cure of included benzoxazine allowed for the preparation of thin films on millimeter-scaled metal rods where the mechanically robust films do not undergo significant melt flow when cured by inductive heating.

Polybenzoxazine modified by phenolphthalein‐based poly(arylene ether nitrile): Better thermal, mechanical, and dielectric properties

“…Polybenzoxazine, as a relatively new member of highperformance thermosetting resins, is attracting more and more attention from academia and industrial communities due to its high molecular design flexibility, high thermal resistance, high modulus, flame retardance, good dielectric properties, and low dimensional change during curing. [1][2][3][4][5][6][7][8][9][10] It shows good potential in automobile industry, rail traffic, electronic materials, and aerospace. [11][12][13][14][15] However, the phenolic Mannich bridge structure generated by ring-opening polymerization of benzoxazine monomers favors the formation of intramolecular six-membered hydrogen bonding, the strong six-membered hydrogen bonding would hinder the chain-propagation and cross-linking, and the low crosslinking density would further hamper the toughness of polybenzoxazine.…”

“…Polybenzoxazine, as a relatively new member of high‐performance thermosetting resins, is attracting more and more attention from academia and industrial communities due to its high molecular design flexibility, high thermal resistance, high modulus, flame retardance, good dielectric properties, and low dimensional change during curing 1‐10 . It shows good potential in automobile industry, rail traffic, electronic materials, and aerospace 11‐15 .…”