{"title":"Cage octasilsesquioxane-pendant polynorbornenes connected with short spacers exhibiting optical transparency","authors":"Yu Tomioka, Ryota Tanaka, Thu Thao Pham, Shin-ichi Yusa, Hiroaki Imoto, Kensuke Naka","doi":"10.1038/s41428-024-00903-y","DOIUrl":null,"url":null,"abstract":"Heptaisobutyl-norbornenylethyl-substituted cage octasilsesquioxane (POSS) (1a) and heptaphenyl-norbornenylethyl-substituted POSS (1b) were subjected to ring-opening metathesis polymerizations (ROMP) at room temperature with the Grubbs 2nd generation catalyst. The metathesis polymerizations of 1a and 1b were performed at room temperature for 3 h with initial monomer molar concentrations of [1a, 1b] = 10 mM, and the number average molecular weights (Mn) of 2a and 2b were 82,000 g/mol and 87,000 g/mol, respectively. Dynamic light scattering (DLS) and static light scattering (SLS) measurements showed that the Rg/Rh value for 2a was 4.91, suggesting the formation of polydisperse rod-shaped particles. Chloroform solutions of 2a and 2b were cast onto glass substrates and dried at room temperature to obtain optically transparent free-standing films. X-ray diffraction (XRD) analyses of the casted films revealed their amorphous natures. Thermogravimetric analyses (TGA) of 2a and 2b under N2 atmospheres showed 5 wt% losses (Td5) at 416 °C and 451 °C, respectively. The POSS-pendant polynorbornenenes connected with short spacers exhibited showed high optical transparencies owing to the prevention of POSS crystallization and the excellent thermal stability. Side-chain typed POSS-based polynorbornenes connecting with a short spacer exhibiting optical transparency owing to prevention of POSS crystallization to provide amorphous character. In addition, the resulting amorphous polymers exhibited excellent thermal stability.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 7","pages":"653-660"},"PeriodicalIF":2.3000,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Polymer Journal","FirstCategoryId":"92","ListUrlMain":"https://www.nature.com/articles/s41428-024-00903-y","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Heptaisobutyl-norbornenylethyl-substituted cage octasilsesquioxane (POSS) (1a) and heptaphenyl-norbornenylethyl-substituted POSS (1b) were subjected to ring-opening metathesis polymerizations (ROMP) at room temperature with the Grubbs 2nd generation catalyst. The metathesis polymerizations of 1a and 1b were performed at room temperature for 3 h with initial monomer molar concentrations of [1a, 1b] = 10 mM, and the number average molecular weights (Mn) of 2a and 2b were 82,000 g/mol and 87,000 g/mol, respectively. Dynamic light scattering (DLS) and static light scattering (SLS) measurements showed that the Rg/Rh value for 2a was 4.91, suggesting the formation of polydisperse rod-shaped particles. Chloroform solutions of 2a and 2b were cast onto glass substrates and dried at room temperature to obtain optically transparent free-standing films. X-ray diffraction (XRD) analyses of the casted films revealed their amorphous natures. Thermogravimetric analyses (TGA) of 2a and 2b under N2 atmospheres showed 5 wt% losses (Td5) at 416 °C and 451 °C, respectively. The POSS-pendant polynorbornenenes connected with short spacers exhibited showed high optical transparencies owing to the prevention of POSS crystallization and the excellent thermal stability. Side-chain typed POSS-based polynorbornenes connecting with a short spacer exhibiting optical transparency owing to prevention of POSS crystallization to provide amorphous character. In addition, the resulting amorphous polymers exhibited excellent thermal stability.
期刊介绍:
Polymer Journal promotes research from all aspects of polymer science from anywhere in the world and aims to provide an integrated platform for scientific communication that assists the advancement of polymer science and related fields. The journal publishes Original Articles, Notes, Short Communications and Reviews.
Subject areas and topics of particular interest within the journal''s scope include, but are not limited to, those listed below:
Polymer synthesis and reactions
Polymer structures
Physical properties of polymers
Polymer surface and interfaces
Functional polymers
Supramolecular polymers
Self-assembled materials
Biopolymers and bio-related polymer materials
Polymer engineering.