Eco-Friendly Tannin-Based Non-Isocyanate Polyurethane Resins for the Modification of Ramie (Boehmeria nivea L.) Fibers

Manggar Arum Aristri; Rita Kartika Sari; Muhammad Adly Rahandi Lubis; Raden Permana Budi Laksana; Petar Antov; Apri Heri Iswanto; Efri Mardawati; Seng Hua Lee; Viktor Savov; Lubos Kristak; Antonios N Papadopoulos

doi:10.3390/polym15061492

Eco-Friendly Tannin-Based Non-Isocyanate Polyurethane Resins for the Modification of Ramie (Boehmeria nivea L.) Fibers

Polymers (Basel). 2023 Mar 16;15(6):1492. doi: 10.3390/polym15061492.

Authors

Affiliations

¹ Department of Forest Products, Faculty of Forestry and Environment, IPB University, Bogor 16680, Indonesia.
² Research Center for Biomass and Bioproducts, National Research and Innovation Agency, Cibinong 16911, Indonesia.
³ Research Collaboration Center for Biomass and Biorefinery between BRIN and Universitas Padjajaran, National Research and Innovation Agency, Cibinong 16911, Indonesia.
⁴ Faculty of Forest Industry, University of Forestry, 1797 Sofia, Bulgaria.
⁵ Department of Forest Products Technology, Faculty of Forestry, Universitas Sumatera Utara, Kwala Bekala, Medan 20145, Indonesia.
⁶ Department of Agro-Industrial Technology, Universitas Padjadjaran, Jatinangor 40600, Indonesia.
⁷ Department of Wood Industry, Faculty of Applied Sciences, Universiti Teknologi MARA (UiTM), Cawangan Pahang Kampus Jengka, Bandar Tun Razak 26400, Malaysia.
⁸ Faculty of Wood Sciences and Technology, Technical University in Zvolen, 96001 Zvolen, Slovakia.
⁹ Laboratory of Wood Chemistry and Technology, Department of Forestry and Natural Environment, International Hellenic University, 661 00 Drama, Greece.

Abstract

This study aimed to develop tannin-based non-isocyanate polyurethane (tannin-Bio-NIPU) and tannin-based polyurethane (tannin-Bio-PU) resins for the impregnation of ramie fibers (Boehmeria nivea L.) and investigate their mechanical and thermal properties. The reaction between the tannin extract, dimethyl carbonate, and hexamethylene diamine produced the tannin-Bio-NIPU resin, while the tannin-Bio-PU was made with polymeric diphenylmethane diisocyanate (pMDI). Two types of ramie fiber were used: natural ramie without pre-treatment (RN) and with pre-treatment (RH). They were impregnated in a vacuum chamber with tannin-based Bio-PU resins for 60 min at 25 °C under 50 kPa. The yield of the tannin extract produced was 26.43 ± 1.36%. Fourier-transform infrared (FTIR) spectroscopy showed that both resin types produced urethane (-NCO) groups. The viscosity and cohesion strength of tannin-Bio-NIPU (20.35 mPa·s and 5.08 Pa) were lower than those of tannin-Bio-PU (42.70 mPa·s and 10.67 Pa). The RN fiber type (18.9% residue) was more thermally stable than RH (7.3% residue). The impregnation process with both resins could improve the ramie fibers' thermal stability and mechanical strength. The highest thermal stability was found in RN impregnated with the tannin-Bio-PU resin (30.5% residue). The highest tensile strength was determined in the tannin-Bio-NIPU RN of 451.3 MPa. The tannin-Bio-PU resin gave the highest MOE for both fiber types (RN of 13.5 GPa and RH of 11.7 GPa) compared to the tannin-Bio-NIPU resin.

Keywords: Acacia mangium bark; cohesion strength; dimethyl carbonate; hexamethylenediamine; non-isocyanate; ramie fiber; tannin-based polyurethane.

Grants and funding

This research was funded by the Indonesian LPDP-RIIM PRN Project, grant number B-1726/II.7.5/FR/11/2022, titled “Teknologi Pengembangan Serat Rami Tahan Api Terimpregnasi Resin Poliuretan Sebagai Bahan Baku Tesktil Fungsional”.