Research

Degradable packaging materials derived from renewable resources 

The objective of this project is to modify polymers derived from renewable resources to achieve the processing, gas barrier, water resistance, biodegradation, and mechanical properties required to enable the wider use of these materials in packaging applications.

Australia, a low cost producer of agricultural products, is well placed to become a producer of polymers derived from renewable resources as they gradually replace polymers derived from declining reserves of fossil fuel. Technology for converting starch into packaging materials has been developed and successfully commercialised in Australia by Plantic. However, applications are limited by factors that include moisture sensitivity. Solutions to these issues would open up new markets for the technology, and could allow for these packing materials to be used with high water content products. Any solution requires that biodegradation standards be met, and that a range of other processing and property requirement be achieved.
 

Degradable polyolefin films for agricultural production 

This research is developing stretched polyolefin films for use in agricultural production that will degrade in a controlled way during, or at the completion of, the growing cycle and so enhance water retention and crop outcomes.

Agricultural films have been laid on a range of crops during or after planting as a way of retaining moisture and acting as a form of ‘greenhouse’ to improve plant growth. The principal benefits include higher, and more reliable, crop yields and soil moisture conservation. Additionally, crops can be planted earlier and thus grown in colder and/or lower rainfall areas with better weed control. Current agricultural films either do not break down or, if they do degrade, they are either made from polymers that are too expensive or do not degrade satisfactorily for widespread usage in large-scale crop production. Photo-degradable polyolefin films have the potential to provide substantial benefits and transform broad-acre production of crops such as wheat and cotton. For this to occur, technologies need to be developed to control and adjust the rate of degradation of the film so that this can be tailored for specific crops and regional differences in climatic conditions. There are currently no commercially available degradation systems for polyolefins that provide the control necessary for widespread use of these degradable films.
 

Functional polymers for photovoltaic devices 

The research objective is to synthesise an efficient, transformable polymeric photovoltaic material.

One of the most significant problems that faces mankind over the next half century is the energy crisis. As a result of the finite fossil fuels reserves and the threat of greenhouse gas emissions, there has been a renewed focus on new energy sources that are clean, cheap and renewable. Conversion of light energy to electrical power is one of the major platforms of a sustainable energy policy, and solar cells are a fast growing segment of the energy market. Today’s photovoltaic materials are based on silicon, limiting applications to rather stiff constructions. An all-polymer solar cell would be transformable to required shapes by low cost polymer processing techniques. The present limitations of all-polymer photovoltaic devices are the lack of understanding of material performance and limitations in long-term stability and efficiency. Improvements in the technology are required to raise the efficiency and lifetime of these solar cells to levels of commercial interest.
 

Polymers for evaporation mitigation technologies 

This project is developing a cost-effective, easy to apply product that will produce ultra-thin chemical films with evaporation control performance at least 20% better than can be achieved using commercially available chemical products.

Australia-wide evaporation from water storages can range from 1.3 to 1.9 metres per annum, with a predicted 4,200 gigalitres of water lost nation-wide over 2004/05. In recent times, the added effect of a national drought has led to declining water reserves due to low rainfall. While a range of structural evaporation mitigation technologies (e.g. floating covers, modules and suspended shadecloth) are available for small storages (<10 ha), many storage dams have surface areas >10 ha and existing structural products are less applicable and require large capital outlays. For such large storages, chemical ultra-thin films (e.g. chemical or polymer-based monolayers), either on their own or in combination with other systems, provide an attractive option.

Commercially available chemical ultra-thin films have been trialled and shown to have wide variability in evaporation reduction (0%-40%). They are applied to the stored water only during periods when the evaporation rates are high and act like a detergent, very efficiently spreading out across the surface to provide a thin (often only a single molecule thick) layer that is not visible and reduces evaporation by restricting the transfer of water into the air.

It has been recognised that the currently available products are less than ideal at preventing water evaporation. Technology for producing more effective ultra-thin films is being developed and trialled in this project through an alliance between three CRCs: Polymers, Irrigation Futures, and Cotton Catchment Communities.