# Development of Bio-Based Thermosetting Resins from Maltodextrin–Itaconate Systems Toward Styrene-Free Unsaturated Polyesters

## TL;DR

This paper introduces a new eco-friendly, low-viscosity resin made from renewable materials that performs as well as traditional petroleum-based resins.

## Contribution

A novel styrene-free, bio-based thermosetting resin with low viscosity and high performance is developed using maltodextrin and dimethyl itaconate.

## Key findings

- The resin achieved a glass transition temperature of 141 °C and decomposition onset near 250 °C.
- It exhibited a flexural strength of 44 MPa and a thermal expansion coefficient as low as 77 ppm/°C.
- The system forms a robust crosslinked network without requiring petroleum-derived diluents.

## Abstract

The transition to sustainable thermosetting resins is frequently hindered by the trade-off between high bio-based content and processability. This study reports a novel strategy in developing a highly bio-based, styrene-free unsaturated polyester resin (UPR) by leveraging maltodextrin-derived mixed esters dissolved in dimethyl itaconate (DMI). Unlike conventional polysaccharide-based systems that suffer from extreme viscosity, our functionalized prepolymer–DMI system achieves a low-viscosity curing solution without requiring petroleum-derived diluents such as styrene. Fourier-transform infrared spectroscopy confirmed the formation of a robust crosslinked network via the complete consumption of C=C bonds. Consequently, the cured resin exhibits exceptional thermal and mechanical performance, outperforming many existing bio-based analogs: a glass transition temperature (Tg) reaching 141 °C, a decomposition onset near 250 °C, and superior dimensional stability with a linear thermal expansion coefficient as low as 77 ppm/°C. Demonstrating a fully renewable, easy-to-process formulation with a flexural strength of 44 MPa, this work provides a design template for the next generation of high-performance, eco-friendly industrial thermosets.