Recent advances in microfluidics have enabled the molecular-level study of polymer dynamics using single DNA chains. Single polymer studies based on fluorescence microscopy allow for the direct observation of non-equilibrium polymer conformations and dynamical phenomena such as diffusion, relaxation, and molecular stretching pathways in flow. Microfluidic devices have enabled the precise contro...

A significant challenge in conventional heat-shrinkable polymers is to produce controllable microstructures. Here we report that the polymer material fabricated by three-dimensional (3D) printing technique has a heat-shrinkable property, whose initial microstructure can undergo a spontaneous pattern transformation under heating. The underlying mechanism is revealed by evaluating internal strain...

The e€ects of ultra-violet irradiation on the microstructure of an oxygen free polymer viz., acrylonitrile-butadiene-styrene and a polymer containing oxygen viz., polycarbonate have been investigated using positron annihilation lifetime measurement. Lifetime results in both polymers in the early stages of irradiation indicate that chain-scission leading to free radical formation is the predomin...

aqueous polymer quenchants are being used increasingly in steel heat treatment industries as a substitution for conventional quenchants. by adjusting the quench parameters of the polymeric media, it is possible to achieve desirable microstructure and mechanical properties in addition to reduction in distortion and cracking. in this work, polyalkylene glycol (pag) aqueous solution was used as th...

Polymer-derived ceramics (PDCs) represent a rather novel class of ceramics which can be synthesized via cross-linking and pyrolysis of suitable polymeric precursors. In the last decades, PDCs have been attaining increased attention due to their outstanding ultrahigh-temperature properties, such as stability with respect to decomposition and crystallization processes as well as resistance in oxi...

Integration of material composition, microstructure, and mechanical properties with geometry information enables design and analysis of materials and products in a computer-aided design (CAD) environment. In this paper, we propose a method for the construction of material models from microstructure images, that can be integrated into a heterogeneous CAD representation. The method utilizes Radon...

The complex, nonlinear flow behavior of soft materials transcends industrial applications, smart material design and non-equilibrium thermodynamics. A long-standing, fundamental challenge in soft-matter science is establishing a quantitative connection between the deformation field, local microstructure and macroscopic dynamic flow properties i.e., the rheology. Here, a new experimental method ...

Polymer materials of reduced size and dimensionality, such as thin films, polymer nanofibres and nanotubes, exhibit exceptional mechanical properties compared with those of their macroscopic counterparts. We discuss here the abrupt increase in Young's modulus in polymer nanofibres. Using scaling estimation we show that this effect occurs when, in the amorphous (non-crystalline) part of the nano...

Aiming to quantitatively evaluate the microstructure of polymer-modified bitumen (PMB) for roads, this paper employs the two-dimensional fast Fourier transform (2DFFT) to process the microscopic and numerical images of four PMBs. The related derivative parameters, including the characteristic frequency and wavelength, are computed from the 2D-FFT power spectrum. The results show that the absenc...

This review covers the development of understanding of polymer morphology of fibrous polymers using Raman Spectroscopy. Morphology refers to form and structure that a polymer exhibit and is influenced by the local microstructure of the back-bone chain. In chain like polymer molecules, the vibration of the carbon chain is easily studied by using Raman spectroscopy. The utility of this technique ...