PROCESS FOR PREPARING A COMPOUND OF THE CLASS OF POLY(GLYCIDYL-METHACRYLATE-CO-ACRYLIC ACID-TER-BUTYL-ACRYLATE)

The invention relates to a process for preparing a compound of the class of poly(glycidyl-methacrylate-co-acrylic acid-ter-butyl-acrylate) with the characteristics of a reactive syntan meant to be applied as a pre-tanning agent for completely delimed neutralized non-pickled pelts. According to the invention, the process consists in mixing 1...0.8 moles of butyl acrylate, 0.6...0.7 moles of acrylic acid neutralized with sodium hydroxide, 0.4...0.5 moles of gycidyl methacrylate in the presence of 4,4'-azobis(4-cyanovaleric) acid initiator in a medium of organic solvent with water traces, the reflux temperature thereof being adjusted to 68°C for a time interval suitable for reaching the adequate average molecular mass, the propagation reaction being interrupted by the temperature drop to 30°C, concomitantly with dosing 0.3 moles of chloroform for each mole of co-monomer mixture, thereby resulting a product which has free oxiranic functional groups to be subsequently separated. Invenţia se referă la un procedeu de obţinere a unui compus din clasa poli(glicidil-metacrilat-co-acid acrilic-ter-butil-acrilat)-ului cu caracteristicile unui sintan reactiv, aplicabil ca agent de pretăbăcire a pieilor gelatină complet decalcificate, neutralizate, dar nepiclate. Procedeul conform invenţiei constă în aceea că se amestecă 1...0,8 moli acrilat de butil, 0,6...0,7 moli acid acrilic neutralizat cu hidroxid de sodiu, 0,4...0,5 moli glicidil metacrilat, în prezenţă de iniţiator acid 4,4'-azobis(4-cianovalerianic), în mediu de solvent organic, cu urme de apă, a cărui temperatură de refluxare se reglează la 68°C, pe o durată convenabilă atingerii masei moleculare medii adecvate, reacţia de propagare întrerupându-se prin scăderea temperaturii la 30°C, concomitent cu dozarea a 0,3 moli cloroform pentru fiecare mol de amestec comonomeri, rezultând un produs care prezintă grupări funcţionale oxiranice libere, care se separă ulterior.