Open Access Received: 27 April 2026   |   Accepted: 12 June 2026   |   Published: 02 July 2026

OPTIMIZATION OF THE SYNTHESIS OF SULFUR CELLULOSE COMPOSITES BY INVERSE VULCANIZATION: INFLUENCE OF TEMPERATURE, TIME, AND COMPONENT RATIO

Saydullo Kh. Azimov¹, Umida R. Baltayeva², Umida Kh. Asranova³

¹ “NEFTGAZ-MALAKA” Training and Research Center, JSC “O‘ZLITINEFTGAZ”, Tashkent, Uzbekistan
² National University of Uzbekistan, Tashkent
³ Andijan State Technical Institute, Andijan, Uzbekistan

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Abstract. This article presents the optimization of sulfur-cellulose composite (SCC) synthesis via inverse vulcanization using waste elemental sulfur (S_8) and activated cotton husk. A three‑factor Box-Behnken design was applied (factors: temperature 160-190°C, time 90-180 min, S:Org mass ratio 40:60-60:40). Regression models were built for three responses: product yield (Y_1), onset decomposition temperature (Y_2, T_{onset}), and fluid loss reduction efficiency (Y_3). All three factors significantly affect composite properties, with temperature being dominant. Optimal synthesis conditions were: T = 185°C, τ = 135 min, S:Org = 55:45. Under these conditions, the composite exhibited a yield of 91.8%, T_{onset} = 272°C, and fluid loss reduction of 62.5%. The use of a catalyst (hexamethylenetetramine, 1 wt% of sulfur) increased yield by 6.6% and thermal stability by 24°C compared to non‑catalyzed synthesis. The composite was characterized by FTIR, TGA, XRD, and SEM-EDX, confirming its formation. The obtained composite is recommended as a thermostable additive for drilling fluids at temperatures up to 180°C.

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Key words. inverse vulcanization; sulfur-cellulose composite; Box-Behnken design; thermal stability; drilling fluid additive; waste valorization; FTIR spectroscopy


DOI: 10.66640/UJP-2026-5-00009

*Corresponding author: Umida R. Baltayeva, National University of Uzbekistan, Tashkent

Citation: Saydullo Kh. Azimov, Umida R. Baltayeva, Umida Kh. Asranova, OPTIMIZATION OF THE SYNTHESIS OF SULFUR CELLULOSE COMPOSITES BY INVERSE VULCANIZATION: INFLUENCE OF TEMPERATURE, TIME, AND COMPONENT RATIO. Uzbekistan Journal of Polymers, Vol. 5(2) 2026: pp.28-37. DOI: 10.66640/UJP-2026-5-00009

©2026 Uzbekistan Journal of Polymers