Thermosetting polycarbodiimide copolymer

A thermosettable polycarbodiimide copolymer containing constituting units each represented by the general formula (I):

• —Y1-A-Y2—Ar—(—N═C═N—Ar—)m— (I)
• wherein Ar represents an arylene group;
• A represents a soft segment containing at least one residue formed by removing opposite functional end groups of polytetramethylene ether glycol, polyether block amide and polyalkylene carbonate diol having at least two alkylene chains selected from the group consisting of hexamethylene, pentamethylene and tetramethylene;
• Y1 and Y2 respectively represent at least one bond having a nitrogen atom bonded to Ar, which is selected from the group consisting of a urethane bond, a urea bond and an amide bond;
• and m is an integer of 1 or more,
• said thermosettable polycarbodiimide copolymer being produced by reacting a polymer exhibiting a liquid state or a flexible solid state at an ordinary temperature which is represented by the general formula (II):
• X1-A-X2 (II)
• wherein X1 and X2 respectively represent a functional group selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group;
• and A is at least one residue formed by removing opposite functional end groups of polytetramethylene ether glycol, polyether block amide and polyalkylene carbonate diol having at least two alkylene chains selected from the group consisting of hexamethylene, pentamethylene and tetramethylene, with an aromatic diisocyanate compound represented by the general formula (III):
• OCN—Ar—NCO (III)
• wherein Ar is the same as defined above, to obtain a both end isocyanate-terminated compound having isocyanate groups on opposite ends thereof which is represented by the general formula (IV):
• OCN—Ar—(Y1-A-Y2—Ar)p—NCO (IV)
• wherein Y1, Y2, Ar and A are the same as defined above;
• and p is an integer of 1 or more;
• and
• subjecting the obtained both end isocyanate-terminated compound to a carbodiimidation reaction in the presence of a carbodiimidation catalyst, wherein said polycarbodiimide copolymer is capable of being thermoset.

A process for producing a thermosettable polycarbodiimide copolymer containing constituting units each represented by the general formula (I):

• —Y1-A-Y2—Ar—(—N═C═N—Ar—)m (I)
• wherein Ar represents an arylene group;
• A represents a soft segment containing at least one residue formed by removing opposite functional end groups of polytetramethylene ether glycol, polyether block amide and polyalkylene carbonate diol having at least two alkylene chains selected from the group consisting of hexamethylene, pentamethylene and tetramethylene;
• Y1 and Y2 respectively represent at least one bond having a nitrogen atom bonded to Ar, which is selected from the group consisting of a urethane bond, a urea bond and an amide bond;
• and m is an integer of 1 or more,
• said process comprising:
• reacting a polymer exhibiting a liquid state or a flexible solid state at an ordinary temperature which is represented by the general formula (II):
• X1-A-X2 (II)
• wherein X1 and X1 respectively represent a functional group selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group;
• and A is at least one residue formed by removing opposite functional end groups of polytetramethylene ether glycol, polyether block amide and polyalkylene carbonate diol having at least two alkylene chains selected from the group consisting of hexamethylene, pentamethylene and tetramethylene, with an aromatic diisocyanate compound represented by the general formula (III):
• OCN—Ar—NCO (III)
• wherein Ar is the same as defined above, to obtain a both end isocyanate-terminated compound having isocyanate groups on opposite ends thereof which is represented by the general formula (IV):
• OCN—Ar—(Y1-A-Y2—Ar)p—NCO (IV)
• wherein Y1, Y2, Ar and A are the same as defined above;
• and p is an integer of 1 or more;
• and
• subjecting the obtained both end isocyanate-terminated compound to a carbodiimidation reaction in the presence of a carbodiimidation catalyst,
• wherein said polycarbodiimide copolymer is capable of being thermoset.