Application of PHSC Equation of State to PEG and PPG Polymers

Macromolecular science has had a major impact on the way we live. It is difficult to find an aspect of our lives that is not affected by polymers. Polyethylene glycol (PEG) and Polypropylene glycol (PPG) have found wide range of applications in medicine, industry and agriculture. PVT (Pressure-Volume-Temperature) properties of polymers are important for both engineering and polymer physics. In addition to experimental measurements, equations of state provide powerful tools for prediction of thermodynamic properties and phase equilibrium calculations, over wide ranges of temperature and pressure.The perturbed hard sphere chain (PHSC) equation of state, proposed by Song et al. [۱] has employed to reproduce the thermophysical properties of a wide variety of normal fluids, including polymers. In the PHSC theory, molecules are assumed to be attracting chains of spheres (segments) that are connected by covalent bonds. Three terms appear in the total pressure equation: Phard-sphere, PChain connectivity and PvdW attraction, respectively due to hard-sphere repulsion, covalent bonds between hard spheres and attractive van der Waals forces between non-bonded hard spheres. The PHSC equation of state for pure fluids has the following form:(...)The segment based parameters, , b and r, have clear physical interpretations. Both and b are temperature dependent and the potential parameters, appear in their equations [۲].

کلیدواژه ها:

Polymer ، Polyethylene glycol (PEG) ، Polypropylene glycol (PPG) ، Perturbed Hard Sphere Chain (PHSC) Equation of State ، Density