{"doi":"10.1295/koron1944.24.606","title":"Some Properties of Isotactic and Syndiotactic Poly (Vinyl Alcohols) and Their Derivatives","abstract":null,"journal":"Kobunshi Kagaku","year":1967,"id":631911,"datarank":2.404914004328373,"base_score":2.833213344056216,"endowment":2.833213344056216,"self_citation_contribution":0.42498200160843247,"citation_network_contribution":1.9799320027199405,"self_endowment_contribution":0.42498200160843247,"citer_contribution":1.9799320027199405,"corpus_percentile":null,"corpus_rank":null,"citation_count":16,"citer_count":13,"citers_with_citation_signal":13,"citers_with_endowment":13,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1637747,"name":"Keiji Matsumura","orcid":null,"position":1,"is_corresponding":false},{"id":1637748,"name":"Ryotaro Ohno","orcid":null,"position":2,"is_corresponding":false},{"id":1637749,"name":"Shun-ichi Nozakura","orcid":null,"position":3,"is_corresponding":false},{"id":1637750,"name":"Shunsuke Murahashi","orcid":null,"position":4,"is_corresponding":false},{"id":1637746,"name":"Masao Sumi","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Some Properties of Isotactic and Syndiotactic Poly (Vinyl Alcohols) and Their Derivatives","abstract":"ビニルトリメチルシリルエーテルのカチオン重合における最適条件を検討して高度のイソタクトおよびシンジオタクトPVAを合成した。これらのPVAの性質を従来の立体規則性PVAのそれと比較検討した。IRスペクトルにおいて高イソタクトPVAは結晶性パンド1145cm-1の他に1160cm-1に新しい弱い吸収がある。シンジオタクトPVAでは立体規則性に関係のある916cm-1の吸収が849cm-1より強くなっている。また, 熱処理するとD916/D849比が小さくなることが見出された。シンジオタクトdiad (%) が増すにつれ, 水に溶けにくくなり, とくに, 74%diadのシンジオタクトPVAは150℃の熱水に不溶で160℃で溶解した。高イソタクトPVAは従来のイソタクトPVAより溶けにくくなることがわかった。示差熱分析から求めた融点はシンジオタクトdiad (%) の増加につれ, 顕著に高くなり, また, 高イソタクトPVAは従来のものより高い融点をもっていて, 20%付近に極小がある。このような融点の上昇, IRおよび溶解性における特異な現象は高イソタクトポリマーにおける新たな結晶状態の徴候を示唆するように思われる。熱天びん分析データから, 高イソタクトおよびシンジオタクトPVAのいずれでも熱安定性のよいことがわかったが, 両者には差異は少ない。誘導されたPVAcのIRには立体規則性による明確な差異は認められなかった。しかし, 溶解性では異なり, 高イソタクトおよびアタクトPVAcはアセトン, ベンゼンに可溶であるが, シンジオタクトPVAcは不溶で, クロロホルム, クロルベンゼンに可溶であった。","is_dataset_classified":null,"base_score":2.833213344056216,"endowment":2.833213344056216,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"19910364","pmcid":null,"openalex_id":"https://openalex.org/W2325591455","authors":[],"funders":[],"total_grants":0,"fwci":0.0,"citation_percentile":0.32732865,"influential_citations":0,"citation_trend":[],"oa_status":"bronze","license":null,"oa_locations":[{"url":"https://www.jstage.jst.go.jp/article/koron1944/24/269/24_269_606/_pdf","host_type":"journal"},{"url":"https://www.jstage.jst.go.jp/article/koron1944/24/269/24_269_606/_pdf","host_type":"publisher"},{"url":"https://doi.org/10.1295/koron1944.24.606","host_type":"journal"}],"fields_of_study":["Synthesis and properties of polymers","biodegradable polymer synthesis and properties","Polymer Science and PVC"],"mesh_terms":[],"keywords":["Diad","Tacticity","Vinyl acetate","Vinyl alcohol","Materials science","Polymer chemistry","Composite material","Copolymer","Polymer","Polymerization"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-06T01:04:41.139115Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}