Gel Characteristics of Urea-Formaldehyde Resin under Shear Flow Conditions
نویسندگان
چکیده
منابع مشابه
Structure formation in urea-formaldehyde resin synthesis
The structure formation in acid promoted polycondensation and particularly in alkaline post-treatment with urea was studied by 13C NMR spectroscopy in the three-step synthesis of ureaformaldehyde resins. Trishydroxymethyl urea was identified as the constituent of the mixture of hydroxylmethylated urea derivatives obtained in alkaline conditions. The formation of methylenes linked to secondary o...
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ژورنال
عنوان ژورنال: Mathematical Problems in Engineering
سال: 2013
ISSN: 1024-123X,1563-5147
DOI: 10.1155/2013/748176