Polymer Journal最新文献_第7页

Polymer alloys with high thermal properties consisting of polyfunctional benzoxazine derived from an oligonuclear phenolic compound and bismaleimide 由低核酚类化合物衍生的多官能团苯并恶嗪和双马来酰亚胺组成的高热稳定性聚合物合金

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-23 DOI: 10.1038/s41428-024-00947-0

Takumi Uramatsu, Sho Morinaga, Taichi Shibatsuka, Takehiro Kawauchi

{"title":"Polymer alloys with high thermal properties consisting of polyfunctional benzoxazine derived from an oligonuclear phenolic compound and bismaleimide","authors":"Takumi Uramatsu, Sho Morinaga, Taichi Shibatsuka, Takehiro Kawauchi","doi":"10.1038/s41428-024-00947-0","DOIUrl":"10.1038/s41428-024-00947-0","url":null,"abstract":"Polymer alloy films were prepared by blending a polyfunctional benzoxazine monomer (OP-p), which was derived from an oligonuclear phenolic compound with a 4,4ʹ-dimethylenebiphenyl group as the phenol linker, and 4,4′-bismaleimidodiphenylmethane (BMI; 10–90 wt.%), followed by thermal curing up to 240 °C. The polymerization behavior was investigated via differential scanning calorimetry and Fourier transform infrared analyses; the results indicated that the obtained polymer alloys consisted of an AB crosslinked network structure formed through the ether linkage between the hydroxyl group of polybenzoxazine and the double bond of BMI. The obtained polymer alloy films were self-standing, homogeneous, and transparent. Based on the dynamic mechanical analysis of the films, the glass transition temperature (Tg) increased to 228 °C and 329 °C for the polymer alloy films with BMI contents of 60 wt.% and 75 wt.%, respectively, which were higher than those of the POP-p or PBMI homopolymer. Despite the improvement in the Tg, the alloy films exhibited sufficient toughness as evidenced via the tensile test. Moreover, thermogravimetric analysis of the polymer alloys revealed that the thermal stability increased with increasing BMI content. High performance polymer alloy films with high Tg, heat resistance, and sufficient toughness were prepared by blending a polyfunctional benzoxazine monomer (OP-p) and 4,4′-bismaleimidodiphenylmethane (BMI; 10–90 wt.%), followed by thermal curing up to 240 °C. The Tg increased to 228 °C and 329 °C for the polymer alloy films with BMI contents of 60 wt.% and 75 wt.%, respectively, which were higher than those of the POP-p or PBMI homopolymer. Despite the improvement in the Tg, the alloy films exhibited sufficient toughness as evidenced via the tensile test.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 12","pages":"1223-1230"},"PeriodicalIF":2.3,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00947-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Role of flexible spacers in achieving photoinduced phase transitions of azobenzene-based liquid-crystalline polymers at room temperature 柔性间隔物在实现室温下偶氮苯基液晶聚合物光诱导相变中的作用

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-23 DOI: 10.1038/s41428-024-00946-1

Yujin Kang, Donguk Kim, Wonho Lee, Changyeon Lee

{"title":"Role of flexible spacers in achieving photoinduced phase transitions of azobenzene-based liquid-crystalline polymers at room temperature","authors":"Yujin Kang, Donguk Kim, Wonho Lee, Changyeon Lee","doi":"10.1038/s41428-024-00946-1","DOIUrl":"10.1038/s41428-024-00946-1","url":null,"abstract":"The photoinduced solid‒liquid phase transition is a fascinating phenomenon that can be utilized for a range of applications, including debondable adhesives, photolithography, and soft actuators; however, developing polymers with this function is not trivial. In this work, we report an azobenzene (Azo)-containing polymer capable of rapid room-temperature photoliquefaction upon UV irradiation and elucidate the design principles for photoliquefying polymers that harness the photothermal effect. We prepare a series of Azo polymers by coupling diacrylate Azo with dithiol-functionalized flexible spacers of different lengths, such as ethylene glycol (EG), hexa(ethylene glycol) (HEG), and poly(ethylene glycol) (PEG). EG-Azo, with the shortest spacer, has a high melting temperature (Tm) of 78 °C due to the strong interactions among the liquid-crystalline Azo molecules. Owing to the high Tm, EG-Azo does not exhibit a photoinduced solid‒liquid phase transition, although it has the greatest photothermal effect among the polymers (temperature rise to 50 °C). The incorporation of the longer spacers effectively decreases the Tm of the Azo polymers. For example, PEG-Azo possesses a reduced Tm of 40 °C, thereby enabling photoliquefaction at room temperature after only 1 min of UV irradiation. PEG-Azo can be reversibly returned to a solid-state within 5 min after the UV light is turned off. This work shows that the length of flexible spacers in azobenzene (Azo)-based polymers is crucial for achieving room-temperature photoliquefaction (i.e., UV light-induced solid‒liquid phase transition). By adjusting the length of dithiol-functionalized flexible spacers, the melting temperature (Tm) of Azo polymers can be effectively modulated. Incorporating longer spacers decreases the Tm to a temperature achievable by the photothermal effect of Azo molecules, thus enabling photoliquefaction of Azo polymers at room temperature.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"1061-1067"},"PeriodicalIF":2.3,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00946-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermoresponsive behavior of dual hydrophilic diblock copolymers prepared via organotellurium-mediated living radical polymerization 通过有机碲介导的活自由基聚合制备的双亲水二嵌段共聚物的热致伸缩行为

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-16 DOI: 10.1038/s41428-024-00952-3

Misato Hayashi, Rintaro Takahashi, Thi Ngan Vu, Kazuaki Matsumura, Shigeru Yamago, Shin-ichi Yusa

{"title":"Thermoresponsive behavior of dual hydrophilic diblock copolymers prepared via organotellurium-mediated living radical polymerization","authors":"Misato Hayashi, Rintaro Takahashi, Thi Ngan Vu, Kazuaki Matsumura, Shigeru Yamago, Shin-ichi Yusa","doi":"10.1038/s41428-024-00952-3","DOIUrl":"10.1038/s41428-024-00952-3","url":null,"abstract":"This study prepared dual thermoresponsive diblock copolymers (E95Nn; n = 93 and 291) comprising poly(ethylene glycol) ethyl ether acrylate (PeDEGA; E) and poly(N-isopropylacrylamide) (PNIPAM; N) blocks with different lower critical solution temperatures (LCSTs). E95Nn was prepared via organotellurium-mediated living radical polymerization through a one-pot synthesis method. Energy-dispersive X-ray spectroscopy revealed that tellurium residue at the polymer chain end was removed during purification via dialysis. The LCST of the PeDEGA was lower than that of PNIPAM. At temperatures below the LCST of PeDEGA, E95Nn dissolved as a single polymer chain (the unimer state). When an aqueous solution of E95Nn was heated, polymer micelles with a PeDEGA core and PNIPAM shells formed above the LCST of the PeDEGA. In pure water, 7–10 polymer micelles formed intermicellar aggregates. The polymer micelles encapsulated hydrophobic guest molecules into the hydrophobic core formed from the PeDEGA chains. Large intermicellar aggregates formed above the LCST of PNIPAM owing to hydrophobic interactions between the PNIPAM shells. It is expected that E95Nn polymer micelles can be applied as drug carriers for thermoresponsive controlled drug release. Dual thermoresponsive diblock copolymers comprising poly(di(ethylene glycol) ethyl ether acrylate) (PeDEGA) and poly(N-isopropylacrylamide) (PNIPAM) blocks with different lower critical solution temperatures (LCSTA and LCSTB) were prepared via organotellurium-mediated living radical polymerization. The LCSTA of the PeDEGA was lower than the LCSTB of PNIPAM. At T < LCSTA, the diblock copolymers dissolve in a unimer state. When the LCSTA ≤ T < LCSTB, polymer micelles with a PeDEGA core and PNIPAM shells formed. Above the LCSTB, intermicellar aggregates formed owing to hydrophobic interactions between the PNIPAM shells.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 12","pages":"1129-1141"},"PeriodicalIF":2.3,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222763","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}

引用次数: 0

Synthesis and controlled radical polymerization of axially chiral monomers with a binaphthyl skeleton 具有双萘基骨架的轴向手性单体的合成和受控自由基聚合反应

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-13 DOI: 10.1038/s41428-024-00944-3

Kuiyong Jia, Zhe Chen, Zhujun Huang, Xiangcheng Pan

{"title":"Synthesis and controlled radical polymerization of axially chiral monomers with a binaphthyl skeleton","authors":"Kuiyong Jia, Zhe Chen, Zhujun Huang, Xiangcheng Pan","doi":"10.1038/s41428-024-00944-3","DOIUrl":"10.1038/s41428-024-00944-3","url":null,"abstract":"The synthesis of optically active polymers from monomers with chiral central centers is a well-established method, but reports on the synthesis of optically active polymers using axially chiral monomers are limited. In this study, we present the controlled radical polymerization of axially chiral monomers derived from the commercially available 1,1′-bi-2-naphthol (BINOL) structure. A series of optically active polymers based on the axially chiral structures were successfully polymerized using cumyl dithiobenzoate (CDB) as a chain transfer agent (CTA) for the reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymerization process resulted in polymers with high conversions and yield controlled molecular weights. The differences observed in the specific optical rotation and the circular dichroism (CD) signal intensity between the polymers and the monomers confirmed the synthesis of optically active polymers with specific structures. Owing to their unique molecular scaffold, these chiral polymers have promising applications in areas such as chiral separation and catalysis. The graphical abstract shows the controlled radical polymerization of axially chiral monomers bearing a 1,1′-bi-2-naphthol (BINOL) skeleton. The evident increase in magnitude and opposite deflection direction of the specific optical rotation between the synthesized polymer and the monomer confirms the synthesis of the chiral polymers with specific structures.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"987-995"},"PeriodicalIF":2.3,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00944-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Soft electroactive polymer actuators based on regioregular/regiorandom-poly(3-hexylthiophene) blends with a nanofiber structure 基于具有纳米纤维结构的正规/非正规聚（3-己基噻吩）共混物的软电活性聚合物致动器

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-13 DOI: 10.1038/s41428-024-00949-y

Yoshihiro Murasawa, Tomoya Yoshii, Takumi Suzuki, Takeshi Shimomura

{"title":"Soft electroactive polymer actuators based on regioregular/regiorandom-poly(3-hexylthiophene) blends with a nanofiber structure","authors":"Yoshihiro Murasawa, Tomoya Yoshii, Takumi Suzuki, Takeshi Shimomura","doi":"10.1038/s41428-024-00949-y","DOIUrl":"10.1038/s41428-024-00949-y","url":null,"abstract":"An ionic electroactive polymer actuator (IEPA) was fabricated in this study using a blend of regioregular-poly(3-hexylthiophene) (RR-P3HT) nanofibers, regiorandom-P3HT (RRa-P3HT), and polybutadiene rubber (PBR). The RR-P3HT nanofiber mat, which was reinforced with RRa-P3HT as tie chains and PBR as a flexible matrix, exhibited a large surface area where the nanofibers contacted the electrolyte. Therefore, efficient actuation is expected to synergize with the superior carrier mobility inherent in the nanofibrous architecture. The blended actuator, which preserved the RR-P3HT nanofiber structure, exhibited a substantial bending angle exceeding 80° following the redox reaction while sustaining reversible actuation for more than 30 cycles. An optimal scan rate below 100 mV s−1 was required to obtain substantial actuation. Therefore, the RR-P3HT nanofibers blended with RRa-P3HT and PBR demonstrated remarkable functionality as an IEPA, which was characterized by a significant bending angle and enduring cyclic actuation capabilities. An ionic electroactive polymer actuator (IEPA) was fabricated using regioregular-poly(3-hexylthiophene) (RR-P3HT) nanofibers. The RR-P3HT nanofiber mat was reinforced with regiorandom-P3HT (RRa-P3HT) as the tie chains and polybutadiene rubber (PBR) as a flexible matrix. The blended actuator, which preserved the RR-P3HT nanofiber structure, exhibited a substantial bending angle exceeding 80° after the redox reaction while sustaining reversible actuation for more than 30 cycles. The RR-P3HT nanofibers that were blended with RRa-P3HT and PBR demonstrated remarkable functionality as an IEPA, characterized by a significant bending angle and enduring cyclic actuation capabilities.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 12","pages":"1187-1195"},"PeriodicalIF":2.3,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222765","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}

引用次数: 0

Divalent vinyl ketones derived from fluorene: a facile synthesis of bifunctional acrylic monomers with high reactivity in thia-/aza-Michael addition and Morita-Baylis-Hillman reactions 源自芴的二价乙烯酮：在噻-/扎-迈克尔加成反应和莫里塔-贝利斯-希尔曼反应中具有高反应活性的双官能丙烯酸单体的简便合成方法

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-08 DOI: 10.1038/s41428-024-00939-0

Masatoshi Ohyama, Rie Yasuda, Shinsuke Miyauchi, Yasuhiro Kohsaka

{"title":"Divalent vinyl ketones derived from fluorene: a facile synthesis of bifunctional acrylic monomers with high reactivity in thia-/aza-Michael addition and Morita-Baylis-Hillman reactions","authors":"Masatoshi Ohyama, Rie Yasuda, Shinsuke Miyauchi, Yasuhiro Kohsaka","doi":"10.1038/s41428-024-00939-0","DOIUrl":"10.1038/s41428-024-00939-0","url":null,"abstract":"Although vinyl ketones (VKs) exhibit excellent reactivity toward radicals and nucleophiles, their application in polymer chemistry has been limited compared with that of acrylates. One of the reasons is the difficulty of the synthesis, particularly that of multivalent VKs. Herein, we report the facile synthesis of divalent VKs via Friedel‒Crafts acylation of fluorene and subsequent elimination reactions. For example, via this approach, 2,7-diacryloyl-9,9-dimethylfluorene was obtained at high yields (78%). Because the monomer was obtained at high purity through recrystallization and washing, the procedure is suitable for industrial applications. The addition of dithiols and diamines via thia- and aza-Michael addition afforded the corresponding polythioesters and polyamines, respectively. In addition, the divalent VKs exhibited high reactivity in the Morita‒Baylis‒Hillman reaction with formaldehyde, affording a diol monomer. The polycondensation of the diol monomer and isophthaloyl dichloride yielded a poly(conjugated-ketone ester). Consequently, the divalent VKs described herein are attractive monomers and monomer precursors with ready accessibility and sufficient electrophilicity. A series of divalent vinyl ketones containing fluorene backbone were synthesized via Friedel-Crafts acylation and subsequent elimination reactions. The divalent vinyl ketones underwent polyaddition with dithiols to yield the corresponding polysulfide via thiol–ene click chemistry. They also exhibited high reactivity in the Baylis-Hillman reaction with formaldehyde to afford a diol monomer, and the polycondensation with isophthaloyl dichloride yielded a poly(conjugated-ketone ester).","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 12","pages":"1111-1116"},"PeriodicalIF":2.3,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00939-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141926087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Solar-driven photocatalytic hydrogen production thiophene-quinoxaline-based polymer dots with tunable molecular weight 太阳能驱动的光催化制氢噻吩-喹喔啉基可调分子量聚合物点

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-08 DOI: 10.1038/s41428-024-00945-2

Islam M. A. Mekhemer, Yi-Chieh Chiu, Mohamed M. Elsenety, Ahmed M. Elewa, Dalia M. Dorrah, Khanh Do Gia Huynh, Dung Chau Kim Hoang, Chia-Chih Chang, Ho-Hsiu Chou

{"title":"Solar-driven photocatalytic hydrogen production thiophene-quinoxaline-based polymer dots with tunable molecular weight","authors":"Islam M. A. Mekhemer, Yi-Chieh Chiu, Mohamed M. Elsenety, Ahmed M. Elewa, Dalia M. Dorrah, Khanh Do Gia Huynh, Dung Chau Kim Hoang, Chia-Chih Chang, Ho-Hsiu Chou","doi":"10.1038/s41428-024-00945-2","DOIUrl":"10.1038/s41428-024-00945-2","url":null,"abstract":"Organic conjugated polymer dots (Pdots) are considered promising photocatalysts for solar-driven hydrogen production. However, the impact of molecular weight on their photocatalytic activity remains unexplored. In this study, four thiophene-quinoxaline (PTQ)-based Pdots (D-A system) with tunable molecular weights were fabricated to elucidate the effects of molecular weight on Pdot photocatalytic activity. These Pdots serve as highly efficient and stable photocatalysts for visible-light-driven hydrogen generation in a solvent-free organic system, which was achieved for the first time. Low-molecular-weight Pdots exhibited minimal aggregation, small particle sizes, uniform morphology, enhanced charge transfer capability, and superior photocatalytic activity with remarkable photostability. Notably, L-PTQ10 and L-PTQ11 demonstrated exceptional hydrogen evolution rates of 15,807 and 10,411 μmol g−¹ h−¹, respectively, when coupled with a Pt cocatalyst. The findings from our DFT and molecular dynamics (MD) calculations strongly support our hypothesis, highlighting the use of low-molecular-weight PTQ-based Pdots as a promising strategy to develop efficient and stable photocatalysts for solar-driven hydrogen production. This study presents the synthesis of thiophene-quinoxaline (PTQ)-based polymer dots (Pdots) with tunable molecular weights (D-A system) for the first time. Remarkably, Low-molecular weight Pdots exhibit minimal aggregation, small size, and enhanced charge transfer, leading to superior photocatalytic activity and remarkable photostability.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"1079-1088"},"PeriodicalIF":2.3,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00945-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis of phosphine sulfide group-containing aromatic poly(ether)s with aliphatic substituents on the phosphorus atoms and low dielectric properties 合成含硫化膦基团的芳香族聚（醚），磷原子上具有脂肪族取代基并具有低介电性能

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-08 DOI: 10.1038/s41428-024-00940-7

Ryoyu Hifumi, Kotaro Ochiai, Ikuyoshi Tomita

{"title":"Synthesis of phosphine sulfide group-containing aromatic poly(ether)s with aliphatic substituents on the phosphorus atoms and low dielectric properties","authors":"Ryoyu Hifumi, Kotaro Ochiai, Ikuyoshi Tomita","doi":"10.1038/s41428-024-00940-7","DOIUrl":"10.1038/s41428-024-00940-7","url":null,"abstract":"Recently, materials with low dielectric properties have attracted particular attention because low dielectric properties are key factors in realizing next-generation communication devices with high-speed and low-loss signal transmission and processing and electronic components with high electrical breakdown voltages. In this study, phosphine sulfide (P=S) group-containing aromatic poly(ether)s with aliphatic substituents on the phosphorus atoms were developed for use as low dielectric materials, taking advantage of the low polarity of the P=S groups and the less polarizable nature of the aliphatic moieties. These polymers have moderate to high molecular weights (number-average molecular weights of 8900–35,000 and weight-average molecular weights of 31,900–178,000), good thermal stability (5% weight loss temperatures of 363–423 °C), and high glass transition temperatures (Tg = 210–219 °C). In addition, some of the polymers exhibited low dielectric constants (ε = 2.64–2.68 at 10 GHz and 2.56–2.59 at 20 GHz) and low dielectric dissipation factors (tanδ = 0.0034–0.0035 at 10 GHz and 0.0036–0.0037 at 20 GHz). These results may indicate that P=S group-containing aromatic poly(ether)s with high aliphatic contents are potentially applicable to electrically insulating materials with good dielectric properties in the GHz frequency range and could contribute to high-performance electronic devices. Phosphine sulfide (P=S) group-containing aromatic poly(ether)s with aliphatic substituents on the phosphorus atoms were developed for use as low dielectric materials, taking advantage of the low polarity of the P=S groups and the less polarizable nature of the aliphatic moieties. These polymers exhibited low dielectric constants (ε = 2.64–2.68 at 10 GHz and 2.56–2.59 at 20 GHz) and low dielectric dissipation factors (tanδ = 0.0034–0.0035 at 10 GHz and 0.0036–0.0037 at 20 GHz).","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"997-1004"},"PeriodicalIF":2.3,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00940-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Changes in amorphous structure and reaction acceleration during bulk polymerization of methacrylates 甲基丙烯酸酯体聚合过程中无定形结构的变化和反应加速度

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-07 DOI: 10.1038/s41428-024-00943-4

Yasuhito Suzuki, Ryutaro Mishima, Shodai Onozato, Jo-chi Tseng, Satoshi Hiroi, Kentaro Kobayashi, Koji Ohara, Akikazu Matsumoto

{"title":"Changes in amorphous structure and reaction acceleration during bulk polymerization of methacrylates","authors":"Yasuhito Suzuki, Ryutaro Mishima, Shodai Onozato, Jo-chi Tseng, Satoshi Hiroi, Kentaro Kobayashi, Koji Ohara, Akikazu Matsumoto","doi":"10.1038/s41428-024-00943-4","DOIUrl":"10.1038/s41428-024-00943-4","url":null,"abstract":"It has long been known that a sudden reaction acceleration (i.e., the Trommsdorff effect) occurs during bulk polymerization of methacrylates. While this effect has been qualitatively explained by an increased macroscopic viscosity and decreased termination rate, the detailed mechanism is still debated. This is because the effect occurs so suddenly that the change in macroscopic viscosity is not sufficient to explain the effect quantitatively. Less attention has been given to the change in the amorphous structure during bulk polymerization. In this study, we investigate the amorphous structure during bulk polymerization of methyl methacrylate (MMA), ethyl methacrylate (EMA), and butyl methacrylate (BMA) via X-ray scattering. The amorphous structure changes dramatically at some point during bulk polymerization. To obtain detailed microscopic information, we applied pair distribution function (PDF) analysis during the bulk polymerization of MMA. Our results suggest that a change in the amorphous structure influences the reaction kinetics during bulk polymerization. Changes in the amorphous structure during the bulk polymerization of methacrylates were analyzed using X-ray scattering. As the polymerization progresses, the relative concentrations of monomer and polymer change. Traditionally, it has been assumed a priori that the change in the amorphous structure of the polymerization solution is smooth and continuous. In contrast, our results indicate that the amorphous structure undergoes a sudden change in the late stage of bulk polymerization. Furthermore, this sudden change in the amorphous structure coincides with the rapid reaction acceleration known as the Trommsdorff effect.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"1005-1015"},"PeriodicalIF":2.3,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00943-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141968957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preparation of small-pore UF membranes with high porosity by modulating the size of nano-CaCO3 in a casting solution 通过调节浇铸溶液中纳米 CaCO3 的尺寸制备高孔隙率小孔超滤膜

IF 2.3 4区化学

Polymer Journal Pub Date : 2024-08-02 DOI: 10.1038/s41428-024-00938-1

Yujie Wu, Shenghuan Wang, Yahui Liu, Yanhong Ji, Benqiao He, Mohammad Younas

{"title":"Preparation of small-pore UF membranes with high porosity by modulating the size of nano-CaCO3 in a casting solution","authors":"Yujie Wu, Shenghuan Wang, Yahui Liu, Yanhong Ji, Benqiao He, Mohammad Younas","doi":"10.1038/s41428-024-00938-1","DOIUrl":"10.1038/s41428-024-00938-1","url":null,"abstract":"High-performance ultrafiltration (UF) membranes show significant potential for high selectivity and permeation. In the present study, small-pore polyethersulfone (PES) UF membranes with narrow size distributions and high surface porosities were successfully prepared from PES casting solutions that contained nano-CaCO3 particles of different sizes and were coagulated in a HCl solution. The nano-CaCO3 particles with different sizes (22.8–6.3 nm) were produced by modulating the HCl/nano-CaCO3 molar ratio in the casting solution. The size of the nano-CaCO3 particles and the amount of CaCl2 produced synergistically affected the viscosity of the casting solution; in addition, these factors regulated the structure and performance of the PES UF membranes. The obtained membranes exhibited small pore sizes with narrow pore size distributions and high surface porosities, as well as high water flux and bovine serum albumin (BSA) rejection. The optimized membrane had a surface pore size of 9.8 nm with an FWHM of 5.5 nm and a high surface porosity of 12.8%. The membrane also exhibited a high water permeance of 737.2 L·m−2·h−1·bar−1 with a BSA rejection of 99.3%, which surpassed those reported for PES membranes in the literature. This work provided a simple and effective method for preparing high-performance UF membranes. In the current work, small-pore polyethersulfone (PES) UF membranes with narrow size distribution and high surface porosity were successfully prepared from PES casting solution with different size of nano-CaCO3 and coagulated in HCl solution. The different sizes of nano-CaCO3 particles (22-6 nm) were produced through modulating HCl/nano-CaCO3 molar ratios in the casting solution. The nano-CaCO3 size and produced CaCl2 could synergistically affect the viscosity of the casting solution and then regulated the structure and performance of the PES UF membranes.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 12","pages":"1143-1152"},"PeriodicalIF":2.3,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141881677","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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