Eur. Phys. J. Plus (2015) 130: 116
https://doi.org/10.1140/epjp/i2015-15116-3

Regular Article

Hydrogenation induced deviation of temperature and concentration dependences of polymer-solvent interactions in poly(vinyl chloride) and a new eco-friendly plasticizer

¹ Key Laboratory of High Performance Polymer Materials and Technology, Nanjing National Laboratory of Microstructures, Department of Polymer Science and Engineering, The School of Chemistry and Chemical Engineering, Nanjing University, 210093, Nanjing, P. R. China
² Key Laboratory of Functional Polymer Materials, Ministry of Education, College of Chemistry and School of Physics, Nankai University, 300071, Tianjin, P. R. China
³ Laboratory of Mesoscopic Chemistry, The School of Chemistry and Chemical Engineering, Nanjing University, 210093, Nanjing, P. R. China

^* e-mail: wangxiaoliang@nju.edu.cn
^** e-mail: xuegi@nju.edu.cn

Received: 22 December 2014
Revised: 26 March 2015
Accepted: 30 April 2015
Published online: 23 June 2015

Abstract

As a substitute for di-2-ethylhexyl phthalate (DOP), a new eco-friendly plasticizer, di(2-ethylhexyl) cyclohexane-1,2-dicarboxylate (DEHHP), was systematically studied in this work, mainly focusing on its interaction with poly(vinyl chloride) (PVC). The temperature and concentration dependences of polymer-solvent interactions in PVC/DEHHP were systematically investigated by rheology, low-field NMR and molecular dynamics simulations, and the results were quite different from those in PVC/DOP. With temperature increasing or PVC concentration decreasing, rheology experiments revealed that polymer-solvent interactions in PVC/DEHHP were weaker than that in PVC/DOP. Low-field ¹H NMR results showed that the number of polymer-solvent complexes decreased as temperature increased. A faster decreasing rate of this number made the polymer-solvent interactions weaker in PVC/DEHHP than in PVC/DOP. Molecular dynamics simulations were further performed to study the role of polymer-solvent hydrogen bonding interactions in the systems. The radial distribution function showed that heating and dilution both resulted in faster molecular motions, and disassociation of the hydrogen bonds in the simplex hydrogen bonding system. Therefore, heating and dilution had an equivalent effect on the polymer-solvent interactions.