Abstract
AbstractPoly(tetramethyl‐p‐silphenylene siloxane) crystal mats initially prepared from benzene/methanol (2:1 v/v), when annealed in small amounts of solvent undergo considerable thickening in the chain direction. When the crystals are annealed above their formation temperature, their physical properties change rapidly at first before reaching an asymptotic limit commensurate with annealing time and type of solvent. Changes in melting temperature, heat of fusion, small‐angle x‐ray spacing, and wide‐angle x‐ray scattering patterns have been monitored for three solvents of varying solvent power, ranging from very good to extremely poor. Upon solution annealing, the original crystals mats equilibrate to more stable dimensions compatible with their environment. The activation energy of crystal thickening in contact with a liquid is estimated to be about an order of magnitude lower than that deduced from dry annealing data. It appears that the crystal surface and the crystalline core of the crystals comprising the mats must participate in the measured severalfold increase in long period noted after annealing. The lower surface (or interfacial) energy of the liquid annealed mats compared to isothermally melt‐crystallized polymer of similar molecular weight has a direct bearing on the polymer morphology and crystallinity.
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 callMore From: Journal of Polymer Science: Polymer Physics Edition
Disclaimer: 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.
