Rheological behavior of semi‐aromatic transparent polyamide

Abstract

ABSTRACT:The rheological behaviors of semi-aromatic transparent polyamide (SATPA) melt are investigated using a capillary rheometer. The effects of shear rate, shear stress, and temperature on the apparent viscosity a of SATPA are discussed. A correlation of non-Newtonian index with temperature is obtained. The results show the shear thinning of SATPA; meanwhile a decreases with increasing temperature and shear rate, and the viscous flow activation energy is further obtained from temperature dependence of the samples. It was concluded that the apparent viscosity a is sensitive to temperature at lower shear rate owing to the higher viscous flow activation energy; on the contrary, the influence of temperature effect on the apparent viscosity becomes minor at higher shear rate due to the lower viscous flow activation energy.

Vibrational Spectra of Poly(ethylene terephthalate) Chains in the Mesomorphic Form

“…For the fully amorphous sample, this all-trans peak is very weak while a very broad band is present with two maxima roughly centered at 1454 and 1443 cm −1 . These two maxima [38] have been attributed to Gt and Gg conformations, [14] which are also prevailing in PET solutions. [37] For the mesomorphic phase, as for the amorphous phase, a broad band is observed but its position is definitely shifted to higher wavenumber.…”

Natural sunlight ageing of control and sterilized poly(ethylene terephthalate): Two‐dimensional infrared correlation spectroscopic investigation

“…This band was the least affected by irradiation 8,18 and no change has been reported to occur on it during crystallization. 1 The 2D correlation analysis was performed using the algorithm developed by Noda,9,14 and calculated using the 2DShige version 1.3 software (Shigeaki Morita, Kwansei-Gakuin University, [2004][2005].The spectral intensity of each sample was corrected by subtracting a reference spectrum taken as the spectrum corresponding to the longest ageing period. 19 The resultant dynamic spectra were then used to develop the 2D correlation spectra (synchronous and asynchronous) based on a discrete Hilbert transform algorithm.…”

“…It is widely used in the manufacture of soft drink bottles due to its excellent water and moisture barrier properties. 1,2 The exposure to sunlight and air during the bottles service life results in a photo-oxidation of PET. Photo-oxidation results in the rupture of the polymeric chain by degradation of methylene groups.…”

Bio‐based transparent polyamide 10T/10I/1012 with high performance

“…Transparent polyamide (TPA) is a special polyamide with outstanding optical transparency. Its average transmittance in visible light is up to 90%, which is better than the transparency of polycarbonate and close to the transparency of poly(methyl methacrylate) . Possessing outstanding mechanical property, excellent heat resistance, good dimensional stability, good corrosion, and abrasion resistance, TPA exhibits enormous advantage in the field of special materials and attracted extensive attention.…”