Source: METABOLIX, INC. submitted to NRP
BLOW MOLDED BIOPRODUCTS FROM RENEWABLE PLASTICS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
0218888
Grant No.
2009-33610-20305
Cumulative Award Amt.
$349,450.00
Proposal No.
2009-01141
Multistate No.
(N/A)
Project Start Date
Sep 1, 2009
Project End Date
Aug 31, 2012
Grant Year
2009
Program Code
[8.8]- Biofuels and Biobased Products
Recipient Organization
METABOLIX, INC.
21 ERIE STREET
CAMBRIDGE,MA 02139-4260
Performing Department
(N/A)
Non Technical Summary
The widespread use of synthetic plastics has increased concerns over their adverse environmental impacts, and dramatic fluctuations in the cost and availability of petrochemical sources for plastic production creates the need for renewable, environmentally-friendly plastics derived from agricultural sources. Blow molded products are used widely in packaging, and are a major component of the plastics manufacturing industry that are suitable for replacement by biobased materials. This project will demonstrate the use of Polyhydroxyalkanoates (PHAs), a family of bioplastics made by the biological conversion of agricultural feedstocks, in commercial-scale blow molding manufacturing operations. Advances in PHA formulation and processing technology developed in Phase 1 of the project demonstrated the feasibility of blow molding PHAs at the lab-scale. In this program, PHA formulations will be improved with the necessary melt strength and crystallization behavior for blow molding operations using existing equipment at current production fficiencies, while providing the key physical properties needed in the blow molded part. Once satisfactory formulations are developed, pilot blow molding trials will be conducted to confirm proper rheological behavior of the PHA formulations and physical properties of the molded part. Metabolix will then demonstrate blow molding on commercial scale equipment running at typical manufacturing speeds.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5111629200065%
5115310202035%
Goals / Objectives
The specific technical objectives of Phase 2 of this project are to develop biobased PHA resin formulations with processing properties suitable for large-scale blow molding operations, demonstrate blow molding at commercial scale, map the physical properties of the blow molded product, and optimize blow molding cycle times to that of commercial production specifications. Metabolix will use a combination of high molecular weight biobased PHAs, in conjunction with reactive extrusion processes, to create blends of branched and linear PHAs with the required rheological properties and melt strength for blow molding operations on commercial scale equipment. These formulations will be further improved in conjunction with blow molding process optimization to achieve commercial line speeds and meet full end-use container physical properties. Success in this project will open up a large segment of the current thermoplastics market to biobased PHA products.
Project Methods
The following tasks are critical to the successful development of PHA resin formulations suitable for blow molding and the production of blow molded products from biobased PHA polymers: 1. Synthesis and molecular characterization of branched PHAs; 2. Production and characterization of blends of linear and branched PHAs of varying molecular weights and compositions; 3. Conduct lab-scale blow molding, measure and map physical properties of item; 4. Conduct commercial-scale blow molding, measure and map physical properties of item; 5. Optimize formulation to meet commercial scale blow molding times. Results obtained from Phase 1 of the program will form the basis for moving forward with Task 1 and 2 to develop formulations that have the desired elastic and viscous properties at the preferred processing conditions for PHAs. Lab-scale blow molding operations similar to that conducted in the Phase 1 project will be conducted to demonstrate improved melt strength and required rheological behavior needed for larger scale blow molding operations. Physical properties of the blow molded object will be measured and mapped as a basis for comparison with a standard PET blow molded object. Once a formulation(s) is identified that has the required combination of melt strength and physical properties, blow molding operations will be conducted on commercial-scale blow molding equipment. Metabolix has worked with several plastics converters with commercial blow molding equipment available for testing these formulations. Once commercial scale objects have been blow molded, the physical properties will be measured and mapped, then compared with PET blow molded items to ensure equivalent product characteristics. The final task will be to optimize the blow molding formulation to increase blow molding production to that obtained by commercial resins. The work proposed in this project will use PHA polymer produced by Metabolix's microbial fermentation process. This material, estimated to be approximately 5000 lbs, will be provided by the Metabolix-ADM commercial production facility scheduled to begin operation in late-2009.

Progress 09/01/09 to 08/31/10

Outputs
OUTPUTS: 1. Bottle wall thickness and weight measurements showed that branched P5001 control sample consistently gave maximum wall thickness and bottle weight while P1004 the minimum. All the rest of samples with various weight blending ratios resulted in wall thickness and bottle weight sat between results of these two control samples. 2. Under the same mold temperature and blow/injection pressure, the differences of wall thickness and weight were narrowed down as extrusion barrel temperature profile was lowered due to reduce melt flow rate. 3. Statistical analysis of various blends of P1004/P5001 and P1004/F3002 showed a consistent trend that increasing the non-branched low melt strength P1004 content reduces bottle wall thickness and weight. Similar trend was observed with P3002/P5001 blends but to a lesser extent. 4. Drop water bottle impact test showed that P5001 has the best impact strength due to its low glass transition temperature, lower shear melt viscosity, and high melt strength due to branching. The negative effect of using stand-alone P5001 compound for blow molding is the resulted lower bottle rigidity, which can be improved through the blending with P1004 or F3002. 5. The processing window of non-branched P1004 is inherently narrow due to low melt strength and high melt viscosity, and can only produce good quality bottles with uniform wall thickness under higher processing temperature. At a loading level of 25~75%, P5001 helps to improve melt flow and increases impact strength of blow molded P1004 bottles under optimal processing conditions. This approach of blending branched and non-branched PHA compounds enables us to control melt rheology of the blended compounds to strike a balance between bottle rigidity and impact strength in the finished bottle products. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Metabolix requested and received a six month no cost extension to map out the process property performance window of the post fabrication annealing step. This study will determine best annealing conditions for improved properties, and a commercially viable annealing system will be set up to demonstrate performance. In addition, a processing guide to assist converters with blow mold operations using our PHA formulation will be developed.

Impacts
With the assistance from CSU and UML in providing extrusion blow molding equipments, man power, and technical support to conduct detailed experimentation and testing on different PHA compounds, we were able to successfully produce extrusion blow molded bottle samples with good processing characteristics, impact strength, rigidity, and aesthetics. The optimal PHA formulations and processing conditions were identified in the current study and ready for the future scale-up trials to verify their performance in the field.

Publications

  • No publications reported this period