Accession Number : ADA194097

Title :   Transport of Organic Vapors in Multiphase Polymer System.

Descriptive Note : Final technical rept. 1 Oct 83-31 Dec 87,

Corporate Author : TUFTS UNIV MEDFORD MA LAB FOR MATERIALS AND INTERFACES

Personal Author(s) : Sung, Nak-Ho ; Meldon, Jerry H

PDF Url : ADA194097

Report Date : Feb 1988

Pagination or Media Count : 11

Abstract : Sorption of organic vapors in glassy-rubbery heterophase polymers is investigated using polystyrene (PS)/Polybutadiene (PB) blends and block copolymers. Experimental data on hexane vapor sorption in phase segregated blends (mixture of dispersed PS microspheres in PB matrix) and block copolymers exhibit non-Fickian characteristics that previous workers with PS/PB copolymers attributed to a diffused interphase. These data, plus results from a model of sorption in heterogeneous media containing a slowly permeable dispersed phase, indicate that the mere presence of two phases with different diffusion time constants is a sufficient condition for apparently non-Fickian behavior. A mold of vapor transport in glassy polymer is presented and employed in conjunction with sorption experiments with PS microspheres in order to determine pertinent diffusion and relaxation constants. Keywords: Transport properties, Heterophase polymers, Block copolymers, Organic vapors, Polystyrene, Polybutadiene, Diffusion, Permeation.

Descriptors :   *BLOCK COPOLYMERS, *POLYBUTADIENE, *POLYSTYRENE, *SORPTION, CONSTANTS, COPOLYMERS, DIFFUSION, DISPERSIONS, EXPERIMENTAL DATA, HETEROGENEITY, HEXANES, MEDIA, MICROSPHERES, MODELS, PHASE, PHASE STUDIES, POLYMERS, RELAXATION, TIME, TRANSPORT, TRANSPORT PROPERTIES, VAPORS, PERMEABILITY, ORGANIC COMPOUNDS

Subject Categories : Elastomers and Rubber
      Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE