Agroplastics: Feasibility of Blending Biomass with Plastic Resins

Grant# 00-04
Principal Investigator: Dora Guffy
Organization: Chariton Valley RC&D
Other Participants: Douglas D. Stokke and Monlin Kuo, Iowa State University
Carey Novak, CATD
Technical Area: Renewable Energy

Background and Significance

This project seeks to determine both the technical feasibility and the commercial viability of using Iowa grown biomass as filler in fiber/plastic composites, thereby reducing the use of energy-intensive, non-renewable raw materials in plastics manufacturing. To date, fossil-based petrochemical resources have represented a convenient and seemingly inexhaustible source for energy and industrial compounds. Concern over a variety of environmental issues as well as the nonrenewable nature of petrochemicals has sparked significant interest in renewable sources of fuels and fiber such as biomass. Biomass can often replace imported petrochemicals while providing a sustainable use for land that should be in grass or trees. Biomass is increasingly seen as a desirable domestic source of energy in the face of foreign instabilities. In addition to already identified opportunities as an energy crop, Iowa grown biomass can provide fiber, fuel and other industrial materials.

Plastics manufactured from petrochemical feedstock are ubiquitous in modern life. Two of the most common thermoplastic materials in use today are polyethylene (PE) and polypropylene (PP). These materials are versatile and economical. They are also energy-intensive in the collection and processing of the raw materials that comprise them. In order to offset some of the energy and economic costs associated with plastics manufacturing, inorganic and organic fillers and reinforcements may be blended with plastics. These additives can also impart desirable changes in physical and mechanical properties of plastics. The activities proposed herein, will demonstrate the technology of using the biomass filler and provide the necessary product testing at a commercial level to encourage the adoption of fiber filler use.

The major benefit for Iowa would be the development of new markets for biomass products that offset the use of petroleum-based plastics in plastics manufacturing. Specifically, Iowa has the raw materials, processors and customer base to initiate a fiber/plastic composites industry. For example, switchgrass is a perennial biomass crop grown in Southern Iowa, with a harvesting infrastructure already in place. This crop, as well as corn stover, could also be used as a fiber source to replace plastic resin.

In Iowa, there are approximately 230 plastic fabricators that use polyethylene, polypropylene and polyurethane to form a wide variety of products. These companies can be targeted as customers of fiber plastics. In addition, the number of wood products processing companies may be considered somewhat similar to the plastic fabricators in the sense that their products may be candidates for fiber/plastic applications.


The overall goal of this project is to demonstrate the process and market feasibility of blending Iowa biomass resources with plastic resins to create value-added feedstock for industrial injection molding and extrusion of compression molding applications. The demonstration will provide sound technical and market information on which entrepreneurs can rely to establish new Iowa-based business ventures to produce and distribute blended fiber/plastic materials.

III. Summary of Work to Date

Objective 1: Technical research program

Task 1, Generate scale-up quantities
Task 2, Conduct testing program

During this reporting period, sample materials (HDPE/wood and HDPE/switchgrass) were blended, injection molded, and provided to Advanced Manufacturing Engineering Services (A.M.E.S.) of Nevada for their in-house evaluation. Following their tests, it is anticipated that the company will request further supplies of material for evaluation in a specific part.

Objective 2: Economic Evaluation

Task 1, Collect properties feedback
Task 2, Document processing costs

The initial phase of processing cost estimates were actually completed during fourth quarter 2001 (Oct.) by Craig Tordsen. Further refinement of his estimates is targeted for the remainder of the project. Stokke and Novak met at the Center for Advanced Technology Development (CATD) offices on June 14 to discuss this portion of the project as well as other areas needing attention in order to complete the entire project successfully by the end of year 3 (June ’03).

Objective 3: Technology Transfer

Task 1, Technical Seminar
Task 3, Evaluate market feedback

As reported last quarter, the technical seminar targeted for March 2002 was scheduled and held at the Iowa Energy Center’s Biomass Energy Conversion (BECON) facility on January 23, 2002. The purpose of the event was to introduce Iowa companies to fiber/plastic materials and research, to showcase the new extruder, and to discuss potential collaborative research and demonstration to be carried out in cooperation with interested companies.