Submitted to: Journal of Polymer Science Part B: Polymer Physics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 14, 2001
Publication Date: N/A
Interpretive Summary: Blends of agricultural biopolymers with petroleum-based polymers can result in materials that can be used in a number of industrial applications. These application areas have performance requirements that often cannot be addressed by agricultural materials alone. To produce blends that have acceptable material properties, good adhesion between the components is a necessity. Presently, little is known about the adhesion and interfacial properties of biopolymers with other materials. Initial studies have been undertaken to explore the role of interfacial adhesion in controlling the mechanical properties of blends of starch with various biodegradable synthetic polymers. Results in this study indicate that interfacial adhesion can play an important role in controlling certain mechanical properties such as peel strength of these blends. The results of this study are important in producing new biobased blends that will be useable in new engineering applications.
Technical Abstract: Biopolymers are preferred ingredients for the manufacture of materials because they are based on abundantly available and renewable raw materials that have benign environmental problems associated with their production, fabrication, use and disposal; however, wide use of biopolymers in engineering applications has not been achieved mainly due to the inferior quality of many biopolymer-based products. In order to overcome this limitation, studies have been initiated on blends of biopolymers and biodegradable synthetic polymers. We have used the contact angle of probe liquids to measure the surface energy of polystyrene, biodegradable polyesters polycaprolactone (PCL), poly(hydroxybutyrate-co-valerate) (PHBHV), polylactic acid (PLA), polybutylene adipate terephthalate (Copolyester 14766), adipic poly(hydroxy ester ether) (PHEE), and normal starch. The surface energies were used to estimate the starch/polymer interfacial energy and work of adhesion. The calculated starch/polyester work of adhesion showed mixed correlation with published starch/polyester mechanical properties, indicating that factors other than interfacial properties might be dominant in the mechanical properties of some starch/polyester blends.