An aromatic polysulfone produced by polymerizing a dihalogeno compound represented by general formula (A) shown below, and a dihydric phenol represented by general formula (B) shown below, the aromatic polysulfone having a value (Mw/Mn) for the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of less than 1.8, and having a number average molecular weight (Mn) of at least 6,000 but less than 14,000. ##STR00001##
(In the formula, each of X and X independently represents a halogen atom; each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represents an alkyl group having a carbon number of 1 to 4 or an alkoxy group having a carbon number of 1 to 4; each of n.sub.1, n.sub.2, n.sub.3 and n.sub.4 independently represents an integer of 0 to 4; and when n.sub.1, n.sub.2, n.sub.3 or n.sub.4 is an integer of 2 to 4, the plurality of R.sup.1, R.sup.2, R.sup.3 or R.sup.4 groups may be the same as, or different from, each other).

An aromatic polysulfone produced by polymerizing a dihalogeno compound represented by general formula (A) shown below, and a dihydric phenol represented by general formula (B) shown below, the aromatic polysulfone having a value (Mw/Mn) for the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of less than 1.8, and having a number average molecular weight (Mn) of at least 6,000 but less than 14,000. ##STR00001##
(In the formula, each of X and X independently represents a halogen atom; each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represents an alkyl group having a carbon number of 1 to 4 or an alkoxy group having a carbon number of 1 to 4; each of n.sub.1, n.sub.2, n.sub.3 and n.sub.4 independently represents an integer of 0 to 4; and when n.sub.1, n.sub.2, n.sub.3 or n.sub.4 is an integer of 2 to 4, the plurality of R.sup.1, R.sup.2, R.sup.3 or R.sup.4 groups may be the same as, or different from, each other).

An aromatic polysulfone produced by polymerizing a dihalogeno compound represented by general formula (A) shown below, and a dihydric phenol represented by general formula (B) shown below, the aromatic polysulfone having a value (Mw/Mn) for the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of less than 1.8, and having a number average molecular weight (Mn) of at least 6,000 but less than 14,000.

##STR00001##

(In the formula, each of X and X independently represents a halogen atom; each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represents an alkyl group having a carbon number of 1 to 4 or an alkoxy group having a carbon number of 1 to 4; each of n.sub.1, n.sub.2, n.sub.3 and n.sub.4 independently represents an integer of 0 to 4; and when n.sub.1, n.sub.2, n.sub.3 or n.sub.4 is an integer of 2 to 4, the plurality of R.sup.1, R.sup.2, R.sup.3 or R.sup.4 groups may be the same as, or different from, each other.) Vertical axis: 5% weight reduction temperature ( C.) Horizontal axis: Mw/Mn

An aromatic polysulfone produced by polymerizing a dihalogeno compound represented by general formula (A) shown below, and a dihydric phenol represented by general formula (B) shown below, the aromatic polysulfone having a value (Mw/Mn) for the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of less than 1.8, and having a number average molecular weight (Mn) of at least 6,000 but less than 14,000.

##STR00001##

(In the formula, each of X and X independently represents a halogen atom; each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represents an alkyl group having a carbon number of 1 to 4 or an alkoxy group having a carbon number of 1 to 4; each of n.sub.1, n.sub.2, n.sub.3 and n.sub.4 independently represents an integer of 0 to 4; and when n.sub.1, n.sub.2, n.sub.3 or n.sub.4 is an integer of 2 to 4, the plurality of R.sup.1, R.sup.2, R.sup.3 or R.sup.4 groups may be the same as, or different from, each other.) Vertical axis: 5% weight reduction temperature ( C.) Horizontal axis: Mw/Mn

A curable polymer composition comprising: (A) a thermoset maleimide resin precursor component; and further comprising one or both of: (B) an arylsulphone-containing maleimide component; and (C) a polyarylpolymer thermoplastic toughening agent component, wherein in the absence of component (B), said component (C) comprises one or more maleimide pendant and/or end groups, and thermoset resins and composites derived therefrom.

A curable polymer composition comprising: (A) a thermoset maleimide resin precursor component; and further comprising one or both of: (B) an arylsulphone-containing maleimide component; and (C) a polyarylpolymer thermoplastic toughening agent component, wherein in the absence of component (B), said component (C) comprises one or more maleimide pendant and/or end groups, and thermoset resins and composites derived therefrom.

A zwitterionic monomer and corresponding cyclopolymerized polyzwitterion () (PZ) (i.e. poly(Z-alt-SO.sub.2). Phosophonate ester hydroloysis in PZ gave a pH-responsive polyzwitterionic acid () (PZA). The PZA under pH-induced transformation was converted into polyzwitterion/anion () (PZAN) and polyzwitterion/dianion (=) (PZDAN).

A zwitterionic monomer and corresponding cyclopolymerized polyzwitterion () (PZ) (i.e. poly(Z-alt-SO.sub.2). Phosophonate ester hydroloysis in PZ gave a pH-responsive polyzwitterionic acid () (PZA). The PZA under pH-induced transformation was converted into polyzwitterion/anion () (PZAN) and polyzwitterion/dianion (=) (PZDAN).

A zwitterionic monomer and corresponding cyclopolymerized polyzwitterion () (PZ) (i.e. poly(Z-alt-SO.sub.2). Phosophonate ester hydroloysis in PZ gave a pH-responsive polyzwitterionic acid () (PZA). The PZA under pH-induced transformation was converted into polyzwitterion/anion () (PZAN) and polyzwitterion/dianion (=) (PZDAN).

A zwitterionic monomer and corresponding cyclopolymerized polyzwitterion () (PZ) (i.e. poly(Z-alt-SO.sub.2). Phosophonate ester hydroloysis in PZ gave a pH-responsive polyzwitterionic acid () (PZA). The PZA under pH-induced transformation was converted into polyzwitterion/anion () (PZAN) and polyzwitterion/dianion (=) (PZDAN).