Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.511
Tatsuhiko Nagao, A. Yagi, Yuhki Kanda, Kuniaki Kawaguchi
and fuel swelling on the molecular mobility and higher-order structure of POM. In this study, the molecular mobility and higher-order structural changes of POM under heating and fuel swelling were analyzed using solid-state NMR, wide-angle X-ray diffraction (WAXD), and small-angle X-ray scattering (SAXS). Solid-state NMR measurements showed that the molecular mobility of all regions including crystalline to amorphous phases was enhanced under heating, while selective enhancement of molecular mobility was observed only in the amorphous and intermediate phases under fuel swelling. The results of solid-state NMR, WAXD, and SAXS measurements also confirmed that higher-order structural changes, such as increased crystallinity and increased volume of amorphous portions which occurred simultaneously due to fuel swelling.
{"title":"Molecular Mobility and Higher-Order Structural Analysis of Polyoxymethylene under Heating and Fuel Swelling","authors":"Tatsuhiko Nagao, A. Yagi, Yuhki Kanda, Kuniaki Kawaguchi","doi":"10.2116/bunsekikagaku.71.511","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.511","url":null,"abstract":"and fuel swelling on the molecular mobility and higher-order structure of POM. In this study, the molecular mobility and higher-order structural changes of POM under heating and fuel swelling were analyzed using solid-state NMR, wide-angle X-ray diffraction (WAXD), and small-angle X-ray scattering (SAXS). Solid-state NMR measurements showed that the molecular mobility of all regions including crystalline to amorphous phases was enhanced under heating, while selective enhancement of molecular mobility was observed only in the amorphous and intermediate phases under fuel swelling. The results of solid-state NMR, WAXD, and SAXS measurements also confirmed that higher-order structural changes, such as increased crystallinity and increased volume of amorphous portions which occurred simultaneously due to fuel swelling.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44991756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.495
Tadatomo Kawai, Shizuka Ukita, S. Shimamoto
A gradient polymer elution chromatography (GPEC) method was developed that can separate cellulose acetate (CA) with respect to a wide range of degrees of substitution (DS). A series of cellulose acetate propionate and cellulose acetate benzoate samples were synthesized by propionylation or benzoylation of CA samples with average degrees of substitution ranging from 0.6 to 2.9, and compositionally separated using the GPEC method. The reversed-phase gradient separation based on an adsorption/desorption mechanism, a linear gradient of acetonitrile : H 2 O = 6 : 1 and ethyl acetate was used with a phenyl group-modified silica column as stationary phase. Separation of samples with different DS values was achieved for both sample series. A slight molar mass effect was observed during elution for the sample with low DS. In addition, a sharp peak at low retention time was observed for the high DS sample. Although a search for further separation systems is necessary for the determination of quantitative substitution degree distribution, this method is applicable to the determination of DS distribution over a wide DS range.
{"title":"Characterization of Chemical Heterogeneity of Cellulose Esters by Gradient Elution HPLC","authors":"Tadatomo Kawai, Shizuka Ukita, S. Shimamoto","doi":"10.2116/bunsekikagaku.71.495","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.495","url":null,"abstract":"A gradient polymer elution chromatography (GPEC) method was developed that can separate cellulose acetate (CA) with respect to a wide range of degrees of substitution (DS). A series of cellulose acetate propionate and cellulose acetate benzoate samples were synthesized by propionylation or benzoylation of CA samples with average degrees of substitution ranging from 0.6 to 2.9, and compositionally separated using the GPEC method. The reversed-phase gradient separation based on an adsorption/desorption mechanism, a linear gradient of acetonitrile : H 2 O = 6 : 1 and ethyl acetate was used with a phenyl group-modified silica column as stationary phase. Separation of samples with different DS values was achieved for both sample series. A slight molar mass effect was observed during elution for the sample with low DS. In addition, a sharp peak at low retention time was observed for the high DS sample. Although a search for further separation systems is necessary for the determination of quantitative substitution degree distribution, this method is applicable to the determination of DS distribution over a wide DS range.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48921115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.501
Tadatomo Kawai, Yuzo Itoh
Poly(styrene- co -methyl acrylate): SMA, poly(styrene- co -tert butyl acrylate): StBA and poly(styrene- co -methyl methacrylate): SMMA were synthesized by reversible addition-fragmentation chain transfer (RAFT) method. The relationship between the molecular weight and the styrene content was investigated by UV–RI dual detection size-exclusion chromatography. In the SMA and StBA of short polymerization time samples, the styrene content showed a tendency to decrease from the low molecular weight region toward the high molecular weight region. On the other hand, the styrene content tended to increase from the low molecular weight region toward the high molecular weight region in the long polymerization time copolymer samples. The SMMA samples showed no trend of similar changes as SMA and StBA. We have concluded that the phenomenon may be due to the difference in the chain length dependence of the equilibrium constants for the pre-equilibrium and main-equilibrium of the RAFT process.
采用可逆加成-破碎链转移法(RAFT)合成了聚苯乙烯- co -丙烯酸甲酯:SMA、聚苯乙烯- co -丙烯酸叔丁酯:StBA和聚苯乙烯- co -甲基丙烯酸甲酯:SMMA。采用UV-RI双检测-排阻色谱法研究了分子量与苯乙烯含量的关系。在短聚合时间的SMA和StBA样品中，苯乙烯含量呈现由低分子量区向高分子量区递减的趋势。另一方面，在长聚合时间的共聚物样品中，苯乙烯的含量有从低分子量区向高分子量区增加的趋势。SMMA样品没有表现出与SMA和StBA相似的变化趋势。我们认为这种现象可能是由于RAFT过程的预平衡和主平衡的平衡常数的链长依赖性不同。
{"title":"Correlation between Molecular Weight and Chemical Composition of Poly(styrene-co-acrylate) Synthesized by RAFT Copolymerization","authors":"Tadatomo Kawai, Yuzo Itoh","doi":"10.2116/bunsekikagaku.71.501","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.501","url":null,"abstract":"Poly(styrene- co -methyl acrylate): SMA, poly(styrene- co -tert butyl acrylate): StBA and poly(styrene- co -methyl methacrylate): SMMA were synthesized by reversible addition-fragmentation chain transfer (RAFT) method. The relationship between the molecular weight and the styrene content was investigated by UV–RI dual detection size-exclusion chromatography. In the SMA and StBA of short polymerization time samples, the styrene content showed a tendency to decrease from the low molecular weight region toward the high molecular weight region. On the other hand, the styrene content tended to increase from the low molecular weight region toward the high molecular weight region in the long polymerization time copolymer samples. The SMMA samples showed no trend of similar changes as SMA and StBA. We have concluded that the phenomenon may be due to the difference in the chain length dependence of the equilibrium constants for the pre-equilibrium and main-equilibrium of the RAFT process.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42808779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.523
T. Ohshiro, Y. Aoyanagi, E. Yamada, F. Ohishi, Y. Nishimoto
As a basic study of the degradation analysis of celluloid, TG measurement and FT-IR measurement by the ATR method were performed on a celluloid sheet irradiated with a xenon lamp and ultraviolet rays, and the results were compared with the cellulose acetate sheet. Celluloid showed a decrease in the thermal decomposition start temperature, and cellulose acetate showed an increase. Information on the deterioration of the sample surface was obtained from the pyrolysis start temperature and the IR spectrum of the surface, and information on the deterioration inside the sample was obtained from the peak temperature of DTG. The results were applied to the actual sample saved. Each celluloid sample was degraded by light, and the degree of degradation was considered to be similar to the change when a 0.2 mm thick sheet was irradiated with a xenon lamp for 8 hours. By devising the measurement conditions, it was confirmed that TG/DTA measurement and celluloid sample are effective measurement methods.
{"title":"Degradation Analysis of Celluloid","authors":"T. Ohshiro, Y. Aoyanagi, E. Yamada, F. Ohishi, Y. Nishimoto","doi":"10.2116/bunsekikagaku.71.523","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.523","url":null,"abstract":"As a basic study of the degradation analysis of celluloid, TG measurement and FT-IR measurement by the ATR method were performed on a celluloid sheet irradiated with a xenon lamp and ultraviolet rays, and the results were compared with the cellulose acetate sheet. Celluloid showed a decrease in the thermal decomposition start temperature, and cellulose acetate showed an increase. Information on the deterioration of the sample surface was obtained from the pyrolysis start temperature and the IR spectrum of the surface, and information on the deterioration inside the sample was obtained from the peak temperature of DTG. The results were applied to the actual sample saved. Each celluloid sample was degraded by light, and the degree of degradation was considered to be similar to the change when a 0.2 mm thick sheet was irradiated with a xenon lamp for 8 hours. By devising the measurement conditions, it was confirmed that TG/DTA measurement and celluloid sample are effective measurement methods.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44598404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.483
Sayaka Nakamura, Hiroaki Sato
High-resolution mass spectrometry is a powerful method for the characterization of polymer materials, but the resulting complex mass spectra bring with it the difficulty of data analysis. Kendrick mass defect (KMD) analysis, which converts complex but informative mass spectra into a two-dimensional plot, can visualize the distribution of multiple components, and has recently attracted attention as a practical polymer characterization technique. Conventional KMD analysis is still insufficient for analysis of industrial polymer materials with complex compositions, so we have proposed several advanced KMD analysis techniques, such as resolution-enhanced KMD (RE-KMD) and remainder of KM (RKM). Sample pretreatment methods have been further developed to observe high quality matrix-assisted laser desorption ionization (MALDI) mass spectra suitable for the KMD analysis. The KMD analyses have been further expanded to other mass spectrometric techniques such as electrospray ionization (ESI)-MS, direct analysis in real time (DART)-MS, and pyrolysis-GC-MS. These achievements are expected to accelerate polymer characterization using high-resolution mass spectrometry.
{"title":"Improvement of Kendrick Mass Defect (KMD) Analysis to Accelerate the Polymer Characterization by High-resolution Mass Spectrometry","authors":"Sayaka Nakamura, Hiroaki Sato","doi":"10.2116/bunsekikagaku.71.483","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.483","url":null,"abstract":"High-resolution mass spectrometry is a powerful method for the characterization of polymer materials, but the resulting complex mass spectra bring with it the difficulty of data analysis. Kendrick mass defect (KMD) analysis, which converts complex but informative mass spectra into a two-dimensional plot, can visualize the distribution of multiple components, and has recently attracted attention as a practical polymer characterization technique. Conventional KMD analysis is still insufficient for analysis of industrial polymer materials with complex compositions, so we have proposed several advanced KMD analysis techniques, such as resolution-enhanced KMD (RE-KMD) and remainder of KM (RKM). Sample pretreatment methods have been further developed to observe high quality matrix-assisted laser desorption ionization (MALDI) mass spectra suitable for the KMD analysis. The KMD analyses have been further expanded to other mass spectrometric techniques such as electrospray ionization (ESI)-MS, direct analysis in real time (DART)-MS, and pyrolysis-GC-MS. These achievements are expected to accelerate polymer characterization using high-resolution mass spectrometry.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42922314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.449
Nobuyuki Kagawa
Synthetic polymers have a molecular weight distribution and, in addition, copolymers composed of multiple monomers have a compositional distribution. Differences in molecular and compositional distributions of these molecular structures in
{"title":"Characterization of Polymer Compositions by Gradient Elution HPLC","authors":"Nobuyuki Kagawa","doi":"10.2116/bunsekikagaku.71.449","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.449","url":null,"abstract":"Synthetic polymers have a molecular weight distribution and, in addition, copolymers composed of multiple monomers have a compositional distribution. Differences in molecular and compositional distributions of these molecular structures in","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42458912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.471
Tomohiro Hirano, Hikaru Momose, Ryota Kamiike, K. Ute
Multivariate analysis was applied to nuclear magnetic resonance (NMR) spectra of methacrylate copolymers. Principal component analysis (PCA) of 13 C NMR spectra of linear copolymers of methyl methacrylate (MMA) and tert -butyl methacrylate (TBMA) successfully extracted information on chemical compositions and monomer sequences. Quantitative analysis of the chemical composition and monomer sequence was achieved by partial least-squares (PLS) regression using NMR spectra of the corresponding homopolymers and their blends as a training dataset. PCA was also useful for the extraction of information on chemical composition in branched copolymers prepared by initiator-fragment incorporation radical copolymerization of TBMA and ethylene glycol dimethacrylate with dimethyl 2,2’-azobis(isobutyrate). The chemical compositions and degree of branching were predicted by PLS regression using NMR spectra of the corresponding homopolymers, their blends and branched copolymers as a training dataset. monomer in of and benzyl methacrylate (BnMA) prepared by various polymer reactions. Furthermore, PCA of 1 H NMR spectra of linear copolymers of MMA and BnMA was applied to extract information on chemical compositions and monomer sequences. Monomer reactivity ratios were reasonably estimated from a single sample using the diad sequence distributions predicted by PLS regression.
{"title":"Determination of Chemical Composition and Monomer Sequence Distributions of Methacrylate Copolymers by Multivariate Analysis of NMR Spectra","authors":"Tomohiro Hirano, Hikaru Momose, Ryota Kamiike, K. Ute","doi":"10.2116/bunsekikagaku.71.471","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.471","url":null,"abstract":"Multivariate analysis was applied to nuclear magnetic resonance (NMR) spectra of methacrylate copolymers. Principal component analysis (PCA) of 13 C NMR spectra of linear copolymers of methyl methacrylate (MMA) and tert -butyl methacrylate (TBMA) successfully extracted information on chemical compositions and monomer sequences. Quantitative analysis of the chemical composition and monomer sequence was achieved by partial least-squares (PLS) regression using NMR spectra of the corresponding homopolymers and their blends as a training dataset. PCA was also useful for the extraction of information on chemical composition in branched copolymers prepared by initiator-fragment incorporation radical copolymerization of TBMA and ethylene glycol dimethacrylate with dimethyl 2,2’-azobis(isobutyrate). The chemical compositions and degree of branching were predicted by PLS regression using NMR spectra of the corresponding homopolymers, their blends and branched copolymers as a training dataset. monomer in of and benzyl methacrylate (BnMA) prepared by various polymer reactions. Furthermore, PCA of 1 H NMR spectra of linear copolymers of MMA and BnMA was applied to extract information on chemical compositions and monomer sequences. Monomer reactivity ratios were reasonably estimated from a single sample using the diad sequence distributions predicted by PLS regression.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48024910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-05DOI: 10.2116/bunsekikagaku.71.461
A. Takahara, R. Ishige, Tomoyasu Hirai, M. Nishibori, Y. Higaki, K. Yamazoe, Y. Harada
X-ray diffraction using tender X-rays, 3) X-ray absorption fine structure (XAFS) analysis of the formation mechanism of poly(3-hexylthiophene) (P3HT), 4) soft X-ray absorption and emission spectroscopic analysis of water structure in polyelectrolyte brushes.
{"title":"Characterization of Soft Materials by Synchrotron Radiation X-ray Based Scattering and Spectroscopic Techniques","authors":"A. Takahara, R. Ishige, Tomoyasu Hirai, M. Nishibori, Y. Higaki, K. Yamazoe, Y. Harada","doi":"10.2116/bunsekikagaku.71.461","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.461","url":null,"abstract":"X-ray diffraction using tender X-rays, 3) X-ray absorption fine structure (XAFS) analysis of the formation mechanism of poly(3-hexylthiophene) (P3HT), 4) soft X-ray absorption and emission spectroscopic analysis of water structure in polyelectrolyte brushes.","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46553403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-05DOI: 10.2116/bunsekikagaku.71.411
Katsutoshi Shimizu, Masahito Ito
{"title":"Optimization Method Based on Visualization of Sensitivity and Separation Performance in HPLC","authors":"Katsutoshi Shimizu, Masahito Ito","doi":"10.2116/bunsekikagaku.71.411","DOIUrl":"https://doi.org/10.2116/bunsekikagaku.71.411","url":null,"abstract":"","PeriodicalId":9521,"journal":{"name":"Bunseki Kagaku","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45270093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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