Valorization of Agricultural Rice Straw as a Sustainable Feedstock for Rigid Polyurethane/Polyisocyanurate Foam Production

Roger G Dingcong Jr; Mary Ann N Ahalajal; Leanne Christie C Mendija; Rosal Jane G Ruda-Bayor; Felrose P Maravillas; Applegen I Cavero; Evalyn Joy C Cea; Kaye Junelle M Pantaleon; Kassandra Jayza Gift D Tejas; Edison A Limbaga; Gerard G Dumancas; Roberto M Malaluan; Arnold A Lubguban

doi:10.1021/acsomega.3c09583

Valorization of Agricultural Rice Straw as a Sustainable Feedstock for Rigid Polyurethane/Polyisocyanurate Foam Production

ACS Omega. 2024 Mar 8;9(11):13100-13111. doi: 10.1021/acsomega.3c09583. eCollection 2024 Mar 19.

Authors

Roger G Dingcong Jr¹, Mary Ann N Ahalajal², Leanne Christie C Mendija³, Rosal Jane G Ruda-Bayor³, Felrose P Maravillas^{2

4}, Applegen I Cavero^{2

5}, Evalyn Joy C Cea², Kaye Junelle M Pantaleon³, Kassandra Jayza Gift D Tejas¹, Edison A Limbaga³, Gerard G Dumancas⁶, Roberto M Malaluan^{1

7}, Arnold A Lubguban^{1

7}

Affiliations

¹ Center for Sustainable Polymers, Mindanao State University - Iligan Institute of Technology, Iligan City 9200, Philippines.
² Department of Civil Engineering and Technology, Mindanao State University - Iligan Institute of Technology, Iligan City 9200, Philippines.
³ Department of Materials Resources Engineering and Technology, Mindanao State University- Iligan Institute of Technology, Iligan City 9200, Philippines.
⁴ College of Engineering, Capitol University, Cagayan de Oro City 9000, Philippines.
⁵ AC Joyo Design and Technical Services, Davao City 8000, Philippines.
⁶ Department of Chemistry, The University of Scranton, Scranton, Pennsylvania 18510, United States.
⁷ Department of Chemical Engineering and Technology, Mindanao State University - Iligan Institute of Technology, Iligan City 9200, Philippines.

Abstract

Agricultural rice straw (RS), often discarded as waste in farmlands, represents a vast and underutilized resource. This study explores the valorization of RS as a potential feedstock for rigid polyurethane/polyisocyanurate foam (RPUF) production. The process begins with the liquefaction of RS to create an RS-based polyol, which is then used in a modified foam formulation to prepare RPUFs. The resulting RPUF samples were comprehensively characterized according to their physical, mechanical, and thermal properties. The results demonstrated that up to 50% by weight of petroleum-based polyol can be substituted with RS-based polyol to produce a highly functional RPUF. The obtained foams exhibited a notably low apparent density of 18-24 kg/m³, exceptional thermal conductivity ranging from 0.031-0.041 W/m-K, and a high compressive strength exceeding 250 kPa. This study underlines the potential of the undervalued agricultural RS as a green alternative to petroleum-based feedstocks to produce a high-value RPUF. Additionally, the findings contribute to the sustainable utilization of abundant agricultural waste while offering an eco-friendly option for various applications, including construction materials and insulation.