ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
An automated microtechnique has been developed that permits a rapid, reproducible determination of the Flory-Huggins χ interaction parameters for poly(vinyl choloride)-plasticizer systems. It is a modification of the Anagnostopoulos method of determining an apparent melting temperature of a poly(vinyl chloride) (PVC) particle in excess plasticizer. A microscope equipped with a photodiode sensor is used to measure changes in the light transmitted through a plasticizer sample containing a PVC particle as the temperature is increased at a fixed rate, either 0.2 or 1.0°C/min. Data acquisition is done by computer so that minimal operator assistance is required. The apparent melting region is characterized by a sigmoidal change in the light transmitted through a fixed sample area. This curve allows an accurate, reproducible definition of the apparent melting temperature from which the χ parameter is easily derived. The values obtained for the interaction parameter of PVC with four plasticizers chosen from the phthalate and phosphate families are in good agreement with general trends of solvent quality. Separate experiments demonstrated that the overall transmittance profile reflects changes in both the size and the optical clarity of the PVC particle during heating. This leads to added features in the profile that reflect important diffusion and swelling characteristics for a given system. © 1994 John Wiley & Sons, Inc.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1994.070521312
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