CORE
🇺🇦
make metadata, not war
Services
Services overview
Explore all CORE services
Access to raw data
API
Dataset
FastSync
Content discovery
Recommender
Discovery
OAI identifiers
OAI Resolver
Managing content
Dashboard
Bespoke contracts
Consultancy services
Support us
Support us
Membership
Sponsorship
Community governance
Advisory Board
Board of supporters
Research network
About
About us
Our mission
Team
Blog
FAQs
Contact us
Closed-loop immiscibility in a ternary mixture of homopolymers
Authors
M. Rabeony Siano, D.B. Peiffer, D.G. Siakah-Kioulafa, E. Hadjichristidis, N.
Publication date
1 January 1994
Publisher
Abstract
Light scattering and calorimetric techniques were used to investigate the isothermal phase behaviour of a ternary polymer blend consisting of three pairwise miscible homopolymers. These homopolymers, polystyrene (PS), poly(2-chlorostyrene) (P2CIS) and polycyclohexylacrylate (PCHA), are apparently the first known examples of homopolymers that form a closed loop in the ternary isothermal phase diagram. The phase diagram of the ternary blend was determined by light scattering at 433 K, where all three pairs are below their respective lower critical solution temperature (LCST). The miscible compositions exhibit a single glass transition temperature (Tg) which follow a simple volume additivity relationship. Inside the immiscible closed-loop region, single Tgs are also observed, but these are shown to be consistent with the presence of two phases. Two binary interaction parameters (for the pairs PS-P2CIS and PS-PCHA) were determined from the locations of LCSTs. The interaction parameter between P2CIS-PCHA was determined by approximating the observed closed-loop region of immiscibility by the Flory-Huggins lattice model. In analogy with systems comprised of a mixture of two polymers and a solvent, the closed-loop immiscibility gap results from an asymmetry in the interaction parameters between the three pairs (a 'Δχ' effect). The following ordering was observed: χPCHA-P2CIS < χPCHA-PS ≈ χPS-P2C1S. This trend is consistent with the curvatures of the composition-dependent glass transition Tg(φ) plots. © 1994
Similar works
Full text
Available Versions
Pergamos : Unified Institutional Repository / Digital Library Platform of the National and Kapodistrian University of Athens
See this paper in CORE
Go to the repository landing page
Download from data provider
oai:lib.uoa.gr:uoadl:3013798
Last time updated on 10/02/2023