1. Necklace-shaped dimethylsiloxane polymers bearing polyhedral oligomeric silsesquioxane cages with alternating length chains
- Author
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Kazuya Suwa, Tsubasa Natsuaki, Shinobu Uemura, Marie Yoshimatsu, Satoshi Watanabe, Takashi Matsuo, Kiyoshi Sakai, Masashi Kunitake, Tomoyuki Ohba, Kunihiro Komori, and Naohiro Katsuta
- Subjects
chemistry.chemical_classification ,Bearing (mechanical) ,Materials science ,Condensation polymer ,Polymers and Plastics ,Organic Chemistry ,Relaxation (NMR) ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Silsesquioxane ,0104 chemical sciences ,law.invention ,Amorphous solid ,chemistry.chemical_compound ,chemistry ,Chain (algebraic topology) ,law ,Polymer chemistry ,Materials Chemistry ,0210 nano-technology ,Glass transition - Abstract
Necklace-shaped dimethylsiloxane (DMS) polymers bearing polyhedral oligomeric silsesquioxane (POSS) cages with “alternating modulated chain” arrangements were synthesized, by the polycondensation of a dimeric POSS precursor and dimethyl oligo-siloxane dichloride. Films of POSS-DMS polymers with “alternating modulated chain” arrangements were highly transparent. This observation is consistent with amorphous structures. Along with “constant chain” and “random chain” type polymers, three different chain arrangements of necklace-shaped polymers can now be produced. The physical properties of the three polymer types with constant POSS cage contents were compared. “Alternating modulated chain” type polymers had lower glass transition temperatures than the other two polymer types. This was attributed to the cooperative relaxation of long chain moieties that comprised half of the connecting chains. “Alternating modulated chain” type POSS-DMS polymers with average chain lengths of three to four exhibited heat resistances of over 470 °C in air.
- Published
- 2017
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