Heat-resistant and strong glassy network copolymers of aromatic ethers (Rolivsans) containing terminal vinyl and methacrylate groups with maleic anhydride

High-temperature properties of rolivsan thermosetting resins (network copolymers of (di)vinylaromatic ethers and cyclized (di)methacrylates)

“…Here, one is tempted to suggest analogy with cyclization of poly(amic acid) into the final polyimide which are complete in solid phase. Thus, cured ROLs are highly crosslinked copolymers containing α-methylenetetralon and methacrylic anhydride units in the main chain and heat resistant bis-(4-vinylphenyl) ether crosslinks (Scheme 3) [17,19,23,24]. Thermal stability of these materials is caused by rigid structure and high density of polymer network including cyclized methacrylate units in the main chain and crosslinks made of (di)vinylaromatic monomeric and oligomeric units.…”

“…It has been found that thermal cure of ROLs leads to the formation of heat resistant network copolymers capable of changing their chemical structure [16][17][18][19], microstructure [20], network density and, accordingly, their thermal and mechanical properties. In the present work, the first detailed studies of the influence of structure and composition as well as cure and post-cure schedules of ROLs on thermal and mechanical properties of the resulting network copolymers and compositions were carried out.…”

“…In the first (relatively low-temperature, 140-170°С) stage of the cure process, thermal copolymerization (free radical crosslinking) of unsaturated components occurs, and copolymers with dense network are formed [17,19]. When temperature is increased up to 180°С, methacrylate crosslinks manifest thermal instability and split with the formation of pending MAA groups and styrene-like monomer (CH 2 =CH-Ar-) units [17,19,23,24]. Then, at 200-250°С and higher temperatures, adjacent MAA units and units containing aromatic styrene-like rings are involved in solid-phase intramolecular cyclization reactions (Friedel-Crafts acylation and dehydration) leading to the formation of α-methylenetetralon and methacrylic anhydride units (Scheme 3).…”

“…Then, at 200-250°С and higher temperatures, adjacent MAA units and units containing aromatic styrene-like rings are involved in solid-phase intramolecular cyclization reactions (Friedel-Crafts acylation and dehydration) leading to the formation of α-methylenetetralon and methacrylic anhydride units (Scheme 3). Pending styrene-like fragments participate in repeated reactions terminating free radical crosslinking (post-cure) [17,19,23,24].…”

Combination of polymerization and polycondensation in the synthesis, chemical modification, and cure of rolivsan thermosetting resins

“…[1][2][3][4] Development of these resins was started in the 1980s. [5][6][7] By now, a vast number of experimental data on rolivsan chemistry have been accumulated, that is, information about mechanisms of their formation [5][6][7][8][9][10][11] and cure, 4,5,[12][13][14] application areas, [1][2][3][4][5] and the new method for chemical modification that has been developed recently. [15][16][17] The present article is a review of our previous investigations and a new development focused for the first time on a substantial contribution of polycondensation to rolivsan chemistry in general and to ROL synthesis in particular.…”