Differential scanning calorimetric and free volume study of reactive compatibilization by EPM-g-MA of poly(trimethylene terephthalate)/EPDM blends

• Published in: Journal of applied polymer science Vol. 100; no. 1; pp. 740 - 747
• Main Authors: Ravikumar, H. B., Ranganathaiah, C., Kumaraswamy, G. N., Deepa Urs, M. V., Jagannath, J. H, Bawa, A. S., Thomas, Sabu
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05-04-2006; Wiley
• Subjects: Applied sciences; compatibilizer; differential scanning calorimetry; Exact sciences and technology; free volume; glass transition temperature; o-Ps lifetime; Organic polymers; Physicochemistry of polymers; Properties and characterization; PTT/EPDM blend; Thermal and thermodynamic properties; PTT/EPDM blend; Propylene copolymer; Polymer blends; Olefin copolymer; Thermal transition; Alkyl terephthalate polymer; o-Ps lifetime; Ester polymer; Free volume; Positron annihilation; Experimental study; Compatibilizer; Functional polymer; glass transition temperature; Heterogeneous mixture; EPDM rubber; Phase separation; differential scanning calorimetry; Concentration effect; Ethylene copolymer; Compatibility
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.23450

Differential scanning calorimetry (DSC) and positron annihilation lifetime measurements have been carried out to study the effect of the compatibilizer maleic anhydride grafted ethylene propylene copolymer (EPM‐g‐MA) in poly trimethylene terephthalate and ethylene propylene diene monomer (PTT/EPDM) immiscible blends. The DSC results for the blends of 50/50 and 30/70 compositions show two clear glass transition temperatures, indicating that the blends are two‐phase systems. With the addition of compatibilizer, the separation between the two glass transitions decreased, suggesting an increased interaction between the blend components with compatibilizer. At 5 wt % of compatibilizer, the separation between the Tgs reduced in both 50/50 and 30/70 blends. The positron results for the blends without compatibilizer showed an increase in relative fractional free volume, as the EPDM content in the blend is increased. This suggests the coalescence of free volume of EPDM with the free volumes of PTT due to phase separation. However, the effect of compatibilizer in the blends was clearly seen with the observed minimum in free volume parameters at 5% of the compatibilizer, further suggesting that this percent of compatibilizer seems to be the optimum value for these blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 740–747, 2006