Abstract
Light-scattering measurements were carried out on polyisoprene (PI) samples with weight-averaged molecular weights (Mws) ranging from 1.1 × 103 to 2.7 × 104 in 1,4-dioxane at and near the theta point, 35.3 °C, which is defined as the temperature at which the second virial coefficient A2 for sufficiently high Mw (larger than 1 × 104) vanishes. It was found that A2 at the theta point decreases with decreasing Mw for Mw<1 × 104. This was explained by the effects of both the three-segment interaction and the side-chain end. The binary-cluster integral for the side-chain-end segment and the PI segment was negative, revealing the attractive interactions between them. The third virial coefficient increased with decreasing Mw. This was also attributed to the side-chain-end effect. The second virial coefficient of low-molecular-weight polyisoprene (PI) in 1,4-dioxane at 35.3 °C becomes negative and decreases with decreasing molecular weight, showing that attractive interactions occur between the PI segment and the chain-end segment.
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.
