Flagship Theme: Biopolymers

Flagship leaders: Prof Yves Poirier and Dr Bill Orts

See the publications section for reports and presentations from this theme.

Summary

Until recently, humankind relied largely on renewable products, many of which are synthesized by plants, to produce a variety of useful materials, e.g. rubber and cellulosic fibres and films. It is only with the advent of petrochemistry that synthetic polymers, such as polypropylene and other plastics, have become predominant in our society. The realisation of the finite nature of our petroleum reserve, the increase in cost of this resource, and the environmental issues linked with plastics and petroleum has brought a new impetus to the use of renewable resources for the production of materials. The flagship “biopolymers” aims at studying the various challenges involved in the use of agricultural plants for the production of a range of biopolymers with useful material properties. These include, but are not limited to, the synthesis of polymers with plastics and elastomeric properties such as polyhydroxyalkanoates and rubbers, starch-based plastics, as well as fibres and adhesives based on proteins or poly-amino acids. In particular, the flagship will be addressing the question: how can plant biology/biotechnology contribute to the development of the use of agricultural plants for the production of biopolymers?

User/Consumer benefit

One important aspect of the biopolymers flagship is to identify and analyse the potential benefits to the producer and users of biopolymers based on agricultural plants, including benefits to the agricultural sector, the manufacturing industries and the consumers. As biomass processing becomes more efficient, and new crops or transgenic plants are developed that contain novel, improved, or simply more biopolymer, the resulting bioplastics become increasingly competitive. The quality of bioplastics may be improved not only by materials technology, but also by specific changes to crops and processing technology.

Scientific challenge

Realising cost-effective production of high-performance biopolymers from agricultural plants is a formidable challenge necessitating interdisciplinary research including plant biochemistry and biotechnology, agronomy, chemistry and material science, as well as process engineering. Each of the polymers mentioned above pose different challenges:

Polyhydroxyalkanoates, and proteins such as silk and adhesin do not naturally occur in plants. Producing these materials in the required high concentrations without compromising the agronomic qualities of the plant is a major task. However, this approach stands in competition with alternative production methods in microorganisms.

In the case of starch, plants have already been modified to change the amount, chain length, branching pattern, and composition of the biopolymer. The challenge here is to define modifications of starch that can be implemented in planta, and lead to better starch-based biopolymers

The development of alternatives to Hevea brasiliensis for natural rubber production requires the domestication of new crops. Making H. brasiliensis resistant to important pathogens like South American leaf blight has yet to yield results and requires the application of new technology.

Protein co-products such as zein, the major protein in corn, or soybean meal may become important raw materials for bioplastics as they become available in large amounts as side-products of biofuel production. Plants may be modified to produce protein with superior properties for bioplastics production.

Economic benefits and risk analysis

For each of the different biopolymers studied, economic assessments, environmental impact and life cycle analyses will be examined to identify the respective strength and weaknesses of the various production, use and disposal scenarios.

In the long run, bioplastics will replace plastics based on petroleum. In the short term, access to a domestic supply is especially important in the case of strategic commodities such as natural rubber. Bioplastics reduce the dependence of the EU and US on imports of raw materials, which helps stabilize volatile markets. For the agricultural sector bioplastics provide opportunities to diversify by finding new uses for product and waste streams.

Private sector involvement

Involvement of the private sector is deemed essential for the success of the biopolymer flagship to ensure that the right polymers are targeted and that the appropriate scientific, technical, economic and markets issues are identified and examined.

While some bioplastics based on plant polymers are already commercially available, others require further fundamental research to reach the commercial stage. Here, industry can provide input on targets, feasibility, new raw material streams, and new applications, helping EPOBIO to single out specific products for targeted research and development efforts.

Breakdown of a biopolymer bottle during composting

Accumulation of PHA granules in Rhodobacter shaeroides