Grantee Research Project Results
Final Report: A Novel Environment Friendly Method For Expansion And Molding Of Polymeric Foam
EPA Grant Number: SU833150Title: A Novel Environment Friendly Method For Expansion And Molding Of Polymeric Foam
Investigators: Penumadu, Dayakar , Benson, Roberto
Institution: University of Tennessee
EPA Project Officer: Page, Angela
Phase: I
Project Period: September 30, 2006 through May 30, 2007
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2006) RFA Text | Recipients Lists
Research Category: P3 Challenge Area - Chemical Safety , Pollution Prevention/Sustainable Development , P3 Awards , Sustainable and Healthy Communities
Objective:
The objective of the project is to develop an environment friendly, novel and efficient alternative process for expansion and molding of polymeric foam. Currently, spherical, expandable polymer beads are prepared from liquid monomer suspended in an aqueous medium, containing an expansion agent. The most common expansion agents used are pentane isomers. A major disadvantage of pentane isomers is their high flammability (Flash point –50°C) and volatility. These blowing agents are Volatile Organic Compounds (VOC) and are suspected to be carcinogenic, to be flammable and to contribute to smog. VOC also contribute to the generation of stratospheric ozone. Within the next few years the polymer industries will be forced by new regulations to drastically reduce the level of VOC emission. The current production process of polystyrene foam, which is the major polymeric foam produced, uses steam as the energy source for expansion of solid polystyrene beads. The machinery associated with steam generation and transmission takes up a substantial floor space as well as ceiling space in ducting. Multi step process increases maintenance cost and chances of failure. In addition to the gaseous emissions there is also a substantial amount of solid waste generated during the production of EPS using the existing process. The protection of industry human resource and reduction of flammable emissions require expensive plant ventilation and gas collection systems.
An appropriate approach for reducing the health hazards associated with production of EPS foam is the replacement of the currently used expansion agents. We propose a chemical reagent that is benign, recyclable and susceptible to heating by appropriate electromagnetic radiation. This new process would also lead to a clean, economic and efficient production, drastically reducing raw material cost, cost of maintaining safety standards and reducing shop floor space.
Development of efficient methods for incorporating benign expansion agents within a polymer bead matrix using the principles of polymerization induced phase separation (PIPS) is a fundamental objective. Other objectives include further research and development of efficient energy sources (microwave radiation) for expansion and molding of the beads (Popcorn effect) and developing theoretical understanding for the process. With the ongoing project we also expect to generate environmental awareness among the present and future industrial community through SPE (Society of Plastics Engineers) meetings, seminars, poster presentations and teaching modules incorporated in undergraduate material science classes.
Summary/Accomplishments (Outputs/Outcomes):
Polystyrene (PS) was used as a model polymer for foaming using the proposed technology. Secondary Butyl Alcohol (Isobutanol) was identified as an ideal expansion agent due to its benign nature, chemical appropriateness and high flash point compared to pentane isomers. Polystyrene pellets with highly dispersed isobutanol phases were synthesized by bulk polymerization and PIPS technique. The dispersed phase separation was characterized for two different PIPS kinetics. Literature review of PIPS modeling, revealed prediction of spherical geometry of phase separation and provided theoretical understanding of PIPS based on concentration of isobutanol and kinetics of the polymerization reaction. Characterized microwave radiation was then successfully used to expand solid polymer pellets into expanded polystyrene inside glass test tube molds. Synthesis of spherical beads between threshold size ranges was identified as a fundamental requirement for microwavable polymeric foam. Spherical polystyrene beads of desired microwavable dimensions can be obtained by modification of existing suspension polymerization process. Industrial collaboration was established to address this requirement and currently we are seeking phase two grant in order to pursue progress in this area of research.
Conclusions:
- Phase-1 successfully implemented the proposed research by developing an example polymer (PS) with phase separated expansion agent.
- Laboratory scale Microwave technology was developed to successfully expand the PS pellets.
- Concept of molding the foam was demonstrated with glass tube as the mold shape
- SIGNIFICANT environmental impact is predicted based on assumed savings in pentane emissions, reduction of energy consumption thus leading to use of less fossil fuels, reduction of reduce greenhouse gases, savings in transportation of fuels/raw materials and industrial maintenance.
- Impact on teaching and learning, promotion of sustainability aspect in technology on a major educational campus
- A leading industrial collaborator (Styrochem) was kept informed of the progress and invention disclosure was filed.
Proposed Phase II Objectives and Strategies:
Phase-II objectives and strategies are based on the foundations of Phase I findings.
- The primary task of Phase-II is the optimization process of phase separation geometry and spatial distribution of the expansion agent in the polymer matrix. This shall be dictated by two factors viz. kinetics of polymerization reaction and the concentration of the expansion agent.
- Optimization of lab scale Microwave expansion process and suitable molds for expansion of different geometry foam. The process parameters involved are microwave power, microwave time and process temperature. Purging and collection of expansion agent is another important research objective.
- Industrial collaboration and technology transfer. Utilization of pilot plant and laboratory facilities at the industry front is a major strategy in achieving commercial success in the proposed project.
- Intermediate scale-up for technology transfer and ideas for full scale implementation in the industry.
- Collaboration with environmental engineering faculty (Dr. Terry Miller) to research and demonstrate environmental impact and an analysis of impact on economy of industrialized nations.
Supplemental Keywords:
Industrial nations, packaging, insulation, structural foam, energy management, toxic exposure, human health, stratospheric ozone, industrial regulations, industrial pollution, clean technology, green chemistry, polymer science and engineering, laser induced polymerization, selective heating by radiation, recyclable raw material, training,, RFA, Scientific Discipline, INTERNATIONAL COOPERATION, TREATMENT/CONTROL, Sustainable Industry/Business, POLLUTION PREVENTION, Sustainable Environment, Energy, Environmental Chemistry, Technology, Technology for Sustainable Environment, Chemicals Management, Environmental Engineering, clean technologies, cleaner production, environmentally conscious manufacturing, environmental sustainability, polymer formulation, recycled polymers, alternative materials, clean manufacturing, polymeric materials, polymerization chemistry, energy efficiency, emission reduction, polymer design, green chemistry, polymer industryRelevant Websites:
http://www.styrochem.com/ Exit
Final Report: Maricopa County Environmental Services Department Title V Operating Permit Program Evaluation
http://www.springerlink.com/content/n646331083473m11/ Exit
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.