Authors:
Tamrin
1
;
Barita Aritonang
2
;
Eddiyanto
3
and
Basuki Wirjosentono
4
Affiliations:
1
1Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Jl. Bioteknologi No.1 Kampus USU Padang Bulan, Medan, 20155, Indonesia
;
2
Postgraduate Chemistry Study Program, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara, Jl. Bioteknologi No. 1 Kampus USU, Medan, Faculty of Science, Technology and Information, University of Sari Mutiara, Indonesia
;
3
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Negeri Medan, Medan, Indonesia
;
4
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara Jl. Bioteknologi No.1 Kampus USU Padang Bulan, Medan, 20155, Indonesia
Keyword(s):
Cyclic natural rubber, oleic acid, dicumil peroxide, divinyl benzene, grafting copolymer.
Abstract:
Modification of cyclic natural rubber with oleic acid using initiator dicumyl peroxide and divinilbenzene as a compositer through the melting phase in the internal mixer using the copolymer grafting method at 160 oC for 8 minutes at 80 rpm was carried out with the aim of increasing its compatibility as a paint binder. Variations in the concentration of oleic acid were used 3, 6 and 9 phr while the initiator concentrations of dicumyl peroxide 0.5 phr and divinilbenzena 1.0 phr. Determination of the degree of grafting was carried out by titration method and FT-IR spectra analysis to determine the presence of oleic acid grafting in the cyclic natural rubber chain. The results showed that the process of grafting oleic acid into the chain of cyclic natural rubber molecules with the presence of initiators dicumyl peroxide and divinylbenzene was successfully carried out marked the emergence of new absorption peaks at wave number 1705.07 cm-1 which is a typical uptake of oleic acid indicatin
g the presence of bond vibrations C=O carbonyl group asymmetry derived from oleic acid. The maximum percentage grafting degree is 0.2630 % at 9 phr oleic acid monomer concentration. The degree of grafting increases with increasing concentration of oleic acid. The transition temperature of cyclic natural rubber glass before being grafted with oleic acid is 102.86 0C but after the grafting process using the initiator dicumyl peroxide and divinylbenzene the glass transition temperature decreases to 83.98 0C this proves that the process of grafting oleic acid into the cyclic natural rubber molecule chain has been successfully carried out with the formation of the new CNR-g-AO product.
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