Process for the controlled hardening of unsaturated polyester resins
Abstract
Abstract The invention relates to a process for the controlled hardening of unsaturated polyester resins at temperatures of -5° C. to +150° C. using an organic peroxide initiator. According to the process of the invention an organic dyestuff of the general formula (I), ##STR1## wherein R 1 stands for a group of the general formula (II), ##STR2## and in this formula R 5 is a C 1-4 alkyl group and n is an integer from 1 to 3, R 2 and R 3 each represent a C 1-4 alkyl group, R 4 stands for hydrogen, or R 1 and R 4 form together a group of the general formula (III), ##STR3## and in this formula R 6 , R 7 and R 8 each represent hydrogen or a C 1-4 alkyl group and Z stands for oxygen or sulfur atom or a -NH- group, and X stands for chlorine or bromine, is admixed with the polyester resin and/or the organic peroxide in an amount of 0.001 to 0.05% by weight, calculated for the weight of the polyester resin. Using the method of the invention the composition and homogeneity of the polyester resin/additive mixtures can be observed easily and the progress of cross-linking can be monitored visually through characteristic colors and color changes, respectively.
Inventors
- 👤 Istvan Kovacsay
- 👤 Maria Szajko nee Lorinczi
- 👤 Istvan Dubovszky
- 👤 Laszlo Magdanyi
- 👤 Ferenc Szailer
- 👤 Ede Szatmari
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
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