BIOPOLYOL PREPARATION from NATURAL RUBBER and WASTE RUBBER PRODUCT

Abstract

This research is interested in studying the effects of rubber waste types on the efficiency and feasibility of bio-polyol preparation. The materials selected for the study consisted of natural rubber, waste glove rubber, and waste tire rubber. Bio polyols are low molecular weight oligomers with hydroxyl groups at the end of the chain. The experiment was divided into 2 steps. Step 1: Prepare bio-carbonyl telechelic oligomers from natural rubber, waste glove rubber, and waste tire rubber. Step 2 was the preparation of bio-hydroxyl telechelic oligomers from bio-carbonyl telechelic oligomers. Carbonyl end group formation was examined and analyzed by FT-IR and
¹H-NMR. It was found that natural rubber is more easily oxidized to the carbonyl end group than waste glove rubber and waste tire rubber, respectively. Proton signals can confirm carbonyl group formation at positions 2.1, 2.25–2.49, and 9.8 ppm, which are protons attached to carbonyl groups on both sides of the molecular chain. Molecular weights of all 3 types of bio-carbonyl telechelic oligomers ranged from 1,500–2,500 g/mol—successful preparation of bio-hydroxyl telechelic oligomers. Since no signal was found in the 2.1–2.5 ppm range, proton signals were found at 3.65 and 3.8 ppm instead, which are the positions of -CH₂OH and -CHOH, respectively. The proton signal at 3.65 and 3.8 ppm confirms the formation of hydroxyl groups at the end of the chain. The molecular weight of bio-hydroxyl telechelic oligomers was 1,500–3,500 g/mol. The FT-IR functional group analysis showed the formation of carbonyl groups at the absorbance wave number 1,720 cm^-1, and a change was observed. That shows the formation of hydroxyl groups at the absorbance band in the range of 3,325–3,500 cm^-1.