ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The interdiffusion of poly(oxy-2,6-dimethyl-1,4-phenylene) (PPE) and polystyrene (PS) sequences is the key step in the formation of the commonly called plastic-rubber composite (Kunststoff-Kautschuk-Verbund, K&K-V). This new process bonds PPE and poly(styrene-co-butadiene) rubber (SBR) during the vulcanization of the rubber, without the aid of any adhesive. As PPE and PS are fully mutually compatible polymers, polymer-polymer interdiffusion takes place readily. PS was therefore used as a model system. Electron microscopy clearly demonstrates that the kinetics of the diffusion process are determined by the faster diffusing PS. This was studied in the temperature range of 180°C to 260°C. The interdiffusion coefficients are of the order of 10-13 to 10-10 cm2 · s-1. These are significantly higher than the selfdiffusion coefficients of PPE and PS, which are 10-15 and 10-12 cm2 · s-1, respectively. The interdiffusion coefficients are dependent on temperature and inversely proportional to the PS molecular weight, for PS molecular weights higher than the entanglement value. The diffusion process follows Fick's law. The interdiffusion coefficient is not, or is only weakly, dependent on the concentration. The interdiffusion of PS samples of molecular weights below the entanglement value is observed by a newly developed method based on Fourier transform infrared spectroscopy with attenuated total reflection technique (FTIR-ATR). In this low-molecular-weight region, interdiffusion coefficients as high as 10-7 cm2·s-1 are obtained.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1990.021911218
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