Abstract
Pulsed nuclear magnetic resonance relaxation measurements are presented for a hydrophobic-hydrophilic diblock copolymer of polystyrene and poly(ethylene oxide) along with results for the individual homopolymers. Although observation of the thermal transitions of the homopolymer components in the copolymer reveals a gross incompatibility, the n.m.r. data suggests strong interfacial effects. From the T 1 and T 2 data below the melting point of PEO ( T m = 335K), it was concluded that polystyrene creates localized defects which reduce PEO domain crystallinity to 75% from 93% in the homopolymer. Above T m in the copolymer three motional domains can be distinguished, isolated rigid polystyrene, isolated molten PEO and an intermediate domain. The composition of the intermediate domain suggests that 23% of the polystyrene is plasticized whereas 80–90% of the molten PEO is motionally constrained. The results are interpreted in terms of a spatial segregation of the homopolymer components with a forced interaction at the phase boundary as a result of the covalent linkages tying the two components together.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
