# Sustainable Substitution of Petroleum-Based Processing Oils with Soybean-Derived Alternatives in Styrene–Butadiene Rubber: Effects on Processing Behavior and Mechanical Properties

## TL;DR

This paper explores replacing petroleum oil with soybean oil in rubber tires, showing improved performance and eco-friendly benefits.

## Contribution

The study introduces soybean-derived oils as sustainable alternatives to petroleum-based oils in rubber composites, achieving both technical and commercial success.

## Key findings

- Soybean oil improved processability and tensile strength by over 10% in SBR composites.
- Epoxidized soybean oil enhanced ozone resistance by 35% due to its chemical structure.
- Green tire prototypes with soybean oil showed burst strength over 1000 kPa and stable performance after 5000 km of testing.

## Abstract

This study evaluates the replacement of petroleum-based naphthenic oil with four types of soybean-derived alternatives—virgin soybean oil (SBO), epoxidized SBO (ESBO), expired SBO, and recycled SBO—in styrene–butadiene rubber (SBR) composites. The materials were tested in both staining rubber (SR) and non-staining rubber (NSR) systems to assess processing characteristics, mechanical performance, and environmental durability. Among the alternatives, SBO demonstrated the best overall performance, improving processability and tensile strength by over 10%, while ESBO enhanced ozone resistance by 35% due to its epoxide functionality. Expired and recycled SBOs maintained essential mechanical properties within 90% of virgin SBO values. The full replacement of CH450 with SBO in tire prototypes resulted in burst strength exceeding 1000 kPa and stable appearance after 5000 km of road testing. To validate industrial relevance, the developed green tire was exhibited at the 2025 Taipei International Cycle Show, attracting interest from international buyers and stakeholders for its eco-friendly composition and carbon footprint reduction potential, thereby demonstrating both technical feasibility and commercial viability.