2000 Progress Report: Environmentally Benign Polymeric Packaging from Renewable ResourcesEPA Grant Number: R826733
Title: Environmentally Benign Polymeric Packaging from Renewable Resources
Investigators: Dorgan, John R. , Knauss, Daniel M.
Institution: Colorado School of Mines
EPA Project Officer: Richards, April
Project Period: November 1, 1998 through October 31, 2001 (Extended to June 14, 2003)
Project Period Covered by this Report: November 1, 1999 through October 31, 2000
Project Amount: $275,000
RFA: Technology for a Sustainable Environment (1999) RFA Text | Recipients Lists
Research Category: Nanotechnology , Sustainability , Pollution Prevention/Sustainable Development
Polylactides (PLAs) are a family of degradable plastics produced by the fermentation of corn. The environmental benefits of these polyesters are numerous and include: (1) reduction of municipal landfill volumes when used as packaging materials; (2) fixation of the greenhouse gas carbon dioxide; (3) significant energy savings; (4) production of the monomer from a renewable agriculturally based resource; and (5) improvement of America's farm economy. Figure 1 shows the novel environmentally friendly route to these plastic materials.
The objectives of the project are to provide fundamental properties for polylactides to facilitate the adoption of this environmentally benign plastic material by industry. In particular, the flow properties of importance during processing of plastics into useful articles have been carefully studied. In addition, the permeation of gases through PLA also has been measured. Knowing these properties is important before industries can adopt this new plastic into new or existing products.
Progress Summary:Plastic materials are used in many everyday applications and present a significant solid waste disposal problem in the United States. In excess of 20 percent of the nation's landfills are occupied by plastic waste. Replacement of petroleum-based plastics by long-term degradable materials based on renewable agricultural resources is one aspect of a solution to this environmental challenge. The two applications of near-term interest for PLA are disposable packaging (for food and other consumer goods) and textile fibers (for the manufacture of clothing and other fabric-based products like baby diapers and disposable wipes). This project has pursued the development of a fundamental scientific understanding of the properties of PLA to allow the commercialization of this important material.
In particular, the rheological (flow) properties of PLA that are of interest in shaping and forming articles (in processing the polymer) have been carefully studied. One work focused on the base linear polymer and has been published in Macromolecules (see http://pubs.acs.org/journals/ mamobx/index.html ). The other explored ways to "tune" the important flow properties through blending of different grades; this work will appear in Polymer Engineering and Science.
Also of interest, particularly for packaging applications, are the permeation properties of PLA (the rate at which gases like oxygen and nitrogen pass through). Another study measured such properties for a variety of different gases and grades of PLA. This study is to appear in the Journal of Membrane Science in the near future.
The work has greatly facilitated the commercialization of PLA, and a new polymer production plant capable of producing 300 million pounds per year of the material is under construction in Blair, Nebraska. Details of the progress as well as other examples for the application of PLA are available at www.cdpoly.com.
Future Activities:We will continue to pursue the project objectives, which include providing fundamental properties for polylactides to facilitate the adoption of this environmentally benign plastic material by industry.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
|Other project views:||All 16 publications||10 publications in selected types||All 10 journal articles|
||Dorgan JR, Williams JS, Lewis DN. Melt rheology of poly(lactic acid): entanglement and chain architecture effects. Journal of Rheology 1999;43(5):1141-1155.||
||Dorgan JR, Lehermeier H, Mang M. Thermal and rheological properties of commercial-grade poly(lactic acid)s. Journal of Polymers and the Environment 2000;8(1):1-9.||