Characteristic Rheological Behaviors in Startup Shear of Entangled Polymer Melts
نویسندگان
چکیده
The present work explores the characteristic rheological behaviors of polystyrene (PS) and poly(methyl methacrylate) (PMMA) melts in startup shear. Through a detailed analysis stress overshoot, unexpected non-universal features are observed as follows. For all examined melts, with increasing shear rate, peak increases time decreases. exhibit power-law relation, for which scaling exponent is −1/2 PS when applied rate larger than reciprocal terminal time. Meanwhile, PMMA three regimes −1, −1/4, evident increase rate. Consequently, relation between not universal chemistry dependent, even if normalized by plateau modulus Rouse relaxation This non-universality can be found literature data other entangled polymers.
منابع مشابه
Stress relaxation in entangled polymer melts.
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ژورنال
عنوان ژورنال: Nihon Reoroji Gakkaishi
سال: 2021
ISSN: ['2186-4586', '0387-1533']
DOI: https://doi.org/10.1678/rheology.49.1