Polymer degradation occurs when polymer ciains are broken under the influence of thermal, mechanical, or chemical energy. Chain-end depolymerization and random- and midpoint-chain scission are mechanisms that have been observed in liquid-phase polymer degradation. Here we develop mathematical models, unified by continuous-mixture kinetics, to show how these different mechanisms affect polymer ...
Brittleness of a polymeric material has a direct relationship with the material's performance and furthermore shares an inverse relationship with that material's flexibility. The concept of flexibility of materials has been understood but merely explained with a hand-waving manner. Thus, it has never been defined by a calculation, thereby lacking the ability to determine a definite ...
Abstract This document addresses polymer materials for use in hydrogen service. Section 1 summarizes the applications of polymers in hydrogen infrastructure and vehicle fuel systems and identifies polymers used in these applications. Section 2 reviews the properties of polymer materials exposed to hydrogen and/or high-pressure environments, using information obtained from published, peer ...
Fiber-reinforced polymer (plastic) piping has been identified as a leading candidate for the material system to transport and distribute hydrogen gas for the broad use of the Hydrogen Economy1. Understanding the permeation, or flux, of hydrogen through polymeric materials is vital to the selection or development of appropriate materials for this application. In order to design an effective ...
We present a new style of molecular dynamics and self-assembly simulation, the Lattice Polymer Automaton (LPA). In the LPA all interactions, including electromagnetic forces, are decomposed and communicated via propagating particles, {open_quotes}photons.{close_quotes} The monomer-monomer bondforces, the molecular excluded volume forces, the longer range intermolecular forces, and the polymer ...