| abstract |
The present invention provides: a urea-modified carbodiimide represented by the following general formula <IMAGE> +TR <IMAGE> (wherein each R is a C1-C12 alkyl group or a C3-C10 cycloalkyl group; each Z is a C1-C12 alkylene group, a C3-C10 cycloalkylene group, a C4-C16 alkylene group having a cyclic or non-cyclic structure, or a C8-C16 alkylene group having an aromatic ring; n is an integer of 1-50; and each m is an integer of 1 or 2), and a process for producing the above urea-modified carbodiimide, which comprises (1) reacting an organic aliphatic diisocyanate represented by the following general formulaO=C=N-Z-N=C=Owith a primary or secondary organic aliphatic amine to introduce urea bonds into the organic aliphatic diisocyanate and then carbodiimidizing the resulting product in the presence of a carbodiimidization catalyst, or (2) at least partially carbodiimidizing, in the presence of a carbodiimidization catalyst, said organic aliphatic diisocyanate and then reacting the resulting carbodiimide with a primary or secondary organic aliphatic amine to introduce urea bonds into the carbodiimide. The urea-modified carbodiimide of the present invention is free from the problems of the prior art, has good compatibility with polyester resins and other thermoplastic resins, and can improve the heat resistance and hydrolysis resistance of thermoplastic resins. |