Biodegradable coatings and adhesives from guayule latex for flexible PHA packaging

Overview

This solution delivers biodegradable, sustainable adhesive and coating materials formulated from guayule latex and resin for flexible polyhydroxyalkanoate (PHA) packaging films. Both products are produced from a single set of natural materials sourced and grown in the United States, supporting domestic supply chains and reducing reliance on petroleum-derived alternatives. The adhesive incorporates a bio-based tackifier for strong bonding performance, while the coating uses lecithin as a natural compatibilizing agent to achieve flexibility and clarity. Together, these materials address the growing demand for fully biodegradable flexible packaging solutions across food, consumer goods, and industrial applications.

Technical specifications

Adhesive formulation:

• Guayule resin combined with guayule latex and a bio-based tackifier (such as Aquatac) at ambient conditions
• Hot-meltable and curable in both solid and liquid forms
• Optimized adhesion properties, appearance, and surface tension tailored for flexible PHA packaging
• Designed to release cleanly with the label upon removal
• Tackifier type, viscosity, and pH tuned through design of experiments methodology

Coating material formulation:

• Guayule latex, resin, and lecithin blended at ambient conditions as a multipolymer precursor
• Lecithin functions as a compatibilizing agent to produce a more flexible coating
• Transparent, high molecular weight polymeric coating with high barrier properties
• Variable thickness to meet different packaging performance requirements

Key advantages:

• Streamlined production from a single set of natural U.S.-grown materials
• Compatible with PHA flexible packaging films
• Fully biodegradable and sustainable alternative to conventional petroleum-based adhesives and coatings

Technology readiness level

The technology is at an early-to-mid stage of development. Initial laboratory experiments have demonstrated that guayule latex and resin can be combined with bio-based tackifiers to produce a strong adhesive and with lecithin to produce transparent, high-barrier coatings compatible with PHA flexible films. The research team has proposed using a design of experiments approach to optimize adhesive properties (including tackifier type, viscosity, and pH) and coating performance, with the goal of scaling production to meet industrial demand. Further validation is needed to confirm performance at commercial scale and across diverse packaging applications.