Article
Materials Science, Composites
Minghui Wu, Fei Wu, Qian Ren, Xichen Jia, Haibin Luo, Bin Shen, Long Wang, Wenge Zheng
Summary: The effects of filler content and expansion ratio on the cell structure and electromagnetic interference (EMI) shielding performance of conductive polymer composite (CPC) foams were investigated. The results showed that the CB content and expansion ratio influenced the EMI shielding effectiveness (SE) of the foams, but with different trends at different CB contents.
COMPOSITES COMMUNICATIONS
(2022)
Article
Materials Science, Characterization & Testing
Yichong Chen, Jiabao Yu, Yijie Ling, Shun Yao, Xiulei Jiang, Dongdong Hu, Huifeng Wang, Ling Zhao
Summary: The mechanical properties of microcellular polypropylene prepared by supercritical CO2 compression foaming were studied and a comprehensive calculation model was established to predict the elastic modulus of different foam materials. It was found that the bubble size affected the compressive and flexural elastic modulus, while the counter-acting force of gas had varying effects on different types of elastic modulus.
Article
Agricultural Engineering
Mehrab Madhoushi, Amin Malakani, Ghanbar Ebrahimi, Alimorad Rashidi
Summary: The study evaluated the mechanical properties of a foamed sugarcane bagasse/polypropylene composite enhanced with spherical-shaped carbon nanoparticles (SCNs). Results showed that adding SCNs improved all mechanical strengths of the composite and enhanced impact strength. Moreover, SCNs enhanced the microcellular structure of the composites and increased energy absorption, thereby improving impact strength.
INDUSTRIAL CROPS AND PRODUCTS
(2021)
Article
Materials Science, Multidisciplinary
Mingchao Li, Tuankang Huang, Youlin Qin, Chunhui Shen, Shanjun Gao
Summary: The melt strength, pressure, and gas amount have significant effects on the foaming of polypropylene. Orthogonal tests can be used to study their influence on foaming effect conveniently. Improvements in melt and foaming masterbatch concentration have the greatest impact on cell size and density. The optimal foaming conditions can significantly decrease cell diameter, increase density, and reduce material density. Good closed-cell structure can enhance bending and impact properties of PP, with impact strength notably improved.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2021)
Article
Polymer Science
Chenguang Yang, Qiang Zhang, Wenli Zhang, Ming Xia, Kun Yan, Jing Lu, Guozhong Wu
Summary: Recyclable, high mechanical strength and thermal insulation polypropylene (PP) foams were achieved by supercritical CO2 foaming with the addition of beta nucleating agent (beta-NAs), showing great potential for reducing energy consumption and improving utilization. The obtained PP-beta foam exhibited excellent properties such as high expansion ratio, low thermal conductivity, and strong tensile and compressive strength. The use of physical foaming technology provided a potential solution for the preparation of multifunctional thermal insulation materials.
POLYMER DEGRADATION AND STABILITY
(2021)
Article
Materials Science, Multidisciplinary
Huayin Wen, Min Wang, Shikai Luo, Yuanlin Zhou, Tao Liu
Summary: A scalable and blending route using silicone rubber (SR) with different crosslinking temperature compared to EPDM was developed to improve the mechanical properties of EPDM foams. The addition of SR in the pre-crosslinking process of EPDM forms a complete crosslinking network, enhancing the compatibility between EPDM and SR and improving the mechanical properties of EPDM foams. When comparing SR/EPDM foam with traditional EPDM foam, the former shows significantly increased tensile strength and compressive strength at similar foam densities, reaching a maximum tensile strength and compressive strength of 3.58 MPa and 0.59 MPa, respectively.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2021)
Article
Chemistry, Physical
Harri Junaedi, Muneer Baig, Abdulsattar Dawood, Essam Albahkali, Abdulhakim Almajid
Summary: This work investigated the mechanical properties of reinforced polypropylene composites, showing that PP23 had better adhesion and dispersion with the fillers, resulting in significant improvement in mechanical properties, especially in PP/GNP composites.
Article
Chemistry, Applied
Venkata Chelikani, Piyush Bhardwaj, Lokesh Kumar, Stephen L. W. On, Maneesha S. Mohan, Avitta Olivero, Loane Thake, Sintia Ramadhani, Philip A. Wescombe, Kenneth J. Olejar
Summary: The novel viscoelastic gelling agent NG, developed by combining citric acid and disodium 5-guanylate, has the potential to replace gelatine and significantly increase the shelf-life of minced beef while inhibiting the growth of major spoilage pathogens.
Article
Polymer Science
Yujing Tang, Yaqiao Wang, Shihong Chen, Xiangdong Wang
Summary: In this study, branched PLLA was obtained by mixing linear PLLA with a chain extender, and the crystallization properties were further modified by adding self-assembled nucleating agent. The results showed that TMC-300 was an effective nucleating agent for branched PLLA, and its self-assembled fibers provided numerous nucleation sites for improved crystallinity. An appropriate content of TMC-300 could be self-assembled into a fiber network framework to regulate the crystallization behavior of branched PLLA and increase storage modulus. This study is important for low-density microcellular foaming and the preparation of high-quality microcellular foams.
POLYMER DEGRADATION AND STABILITY
(2022)
Article
Chemistry, Multidisciplinary
Zhaozhi Wang, Guilong Wang, Zhaorui Xu, Chengming Yang, Guoqun Zhao
Summary: In this study, microcellular foaming with carbon dioxide as blowing agents was developed to prepare structure-tunable PBAT foams with enhanced mechanical performance. The dependence of cellular morphology on foaming conditions was investigated, and the effects of cellular morphology on tensile and compressive properties were clarified. The prepared PBAT foams showed lower density but obviously enhanced mechanical properties compared to previous studies.
JOURNAL OF CO2 UTILIZATION
(2023)
Article
Chemistry, Multidisciplinary
Yifan Jiang, Xiaodong Zhang, Dafu Xu, Wenzhang Li, Min Liu, Xiaoqing Qiu
Summary: Bi-C catalysts show remarkable electrocatalytic CO2 reduction to formate selectivity with high current in a broad potential range at three-phase interfaces.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Przemyslaw Rumianek, Tomasz Dobosz, Radoslaw Nowak, Piotr Dziewit, Andrzej Arominski
Summary: This study aimed to investigate the influence of loading strain rate, material density, and microstructure on the mechanical properties of closed-cell polymeric foams. It was found that increasing strain rate and foam density raised compressive strength and energy absorption capacity, while increasing temperature caused a decrease in these properties. Differences in foam microstructures also led to variations in strength and energy absorption capacity during testing at the same loading strain rate.
Article
Materials Science, Multidisciplinary
Jingqian Deng, Junyi Guo, Zhongjie Du, Chen Zhang, Shengke Liang, Peng Kong, Wei Zou
Summary: A novel organic silicon-carbon foam stabilizer was introduced to improve the properties of polypropylene foam. The foam stabilizer significantly reduced the size, size distribution, and density of the cells, resulting in improved mechanical properties.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2022)
Article
Materials Science, Composites
Abbas Ghanbari, Shayan Seyedin, Mohammadreza Nofar, Amir Ameli
Summary: This research focuses on lightweight products for the transportation industry, introducing recycled carbon fibers and elastomers to polypropylene matrix to improve strength and toughness. The addition of 20 wt% recycled carbon fibers led to significant enhancements in heat distortion temperature, tensile strength, and stiffness. Fractography analysis revealed that the presence of fibers predominantly governs the impact resistance characteristics of the composites.
POLYMER COMPOSITES
(2021)
Article
Polymer Science
Fang Liu, Zhi-gang Zhao, Xue Yang, Ge Pan, Tong-fei Shi, Dong-hua Xu, Wen-tao Zhai
Summary: A series of microcellular thermoplastic polyurethane foams with different densities were prepared using high-pressure CO2 as blowing agent. The relationship between apparent density and mechanical properties was investigated, showing that the thickness ratio of the skin layer and the area occupation of cell play a key role in determining foam density.
ACTA POLYMERICA SINICA
(2021)
Article
Polymer Science
Shinsuke Nagamine, Yosuke Mizuno, Yuta Hikima, Kiyomi Okada, Long Wang, Masahiro Ohshima
Summary: Cellulose microfibers modified with polydopamine and octadecylamine showed improved dispersibility and reinforcing effects in polypropylene matrix. Proper alkylation can enhance the tensile modulus of the composite, while excess alkylation may decrease the performance. Composites fabricated by injection molding exhibited better tensile properties compared to those prepared by batch mixing.
JOURNAL OF APPLIED POLYMER SCIENCE
(2021)
Article
Chemistry, Applied
Qian Ren, Minghui Wu, Zhengsheng Weng, Xiuyu Zhu, Wanwan Li, Pengke Huang, Long Wang, Wenge Zheng, Masahiro Ohshima
Summary: The addition of cellulose nanofibers (CNFs) significantly reduced the half-crystallization time of the PLLA/PDLA blend, and when 3% modified CNFs were incorporated, almost exclusively SC crystallites were formed with no HC crystallite presence. This was speculated to be due to enhanced interchain molecular interactions between CNFs and PLA, presenting a feasible and efficient method for producing high-performance PLA materials with exclusively SC crystallites.
CARBOHYDRATE POLYMERS
(2022)
Article
Chemistry, Multidisciplinary
Koji Nishida, Yuta Hikima, Tsuyoshi Koga, Masahiro Ohshima
Summary: By combining the nonequilibrium nature of a polymeric material and a rapid temperature-jump technique, a polymer crystallite with a ring-like morphology was obtained, and the phenomenon of melting point inversion was observed.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Engineering, Chemical
Mina Farahani, Yousef Jahani, Ali Kakanejadifard, Masahiro Ohshima
Summary: This study investigates the influence of a temperature-sensitive nucleating agent on the crystallization and rheological properties of polypropylene. The self-assembly behavior of the nucleating agent molecules is found to have a significant impact on the rheology of molten polypropylene. By controlling the nucleating agent content and process temperature, the formation of larger fibrils and increased viscosity and storage modulus can be achieved.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Polymer Science
Dongho Kim, Yuta Hikima, Masahiro Ohshima
Summary: In this study, microcellular foams with unique cellular structures were prepared from blends of poly(lactic acid) (PLA) and poly(butylene succinate-co-adipate) (PBSA). The blend morphologies and cellular structures were investigated for different blend ratios, with a 50/50 PLA/PBSA blend showing a layered structure. By utilizing the unique blend morphology and viscosity differences of the polymers, a millefeuille-like microcellular structure was created, resulting in foams with unique anisotropic mechanical properties.
JOURNAL OF APPLIED POLYMER SCIENCE
(2022)
Article
Engineering, Chemical
Xiao Yuan Chen, Shinsuke Nagamine, Masahiro Ohshima, Denis Rodrigue
Summary: In this study, silica xerogels and PE-silica xerogel foams were successfully prepared using various precursors, surfactants, and solvents, showing excellent thermal insulation properties compared to conventional insulation materials. The presence of silica xerogel led to improved compressive modulus and density of the PE foam, making them promising candidates for cost-effective thermal insulation applications.
POLYMER ENGINEERING AND SCIENCE
(2022)
Article
Chemistry, Applied
Qian Ren, Minghui Wu, Long Wang, Wenge Zheng, Yuta Hikima, Takeshi Semba, Masahiro Ohshima
Summary: Adding biodegradable cellulose nanofibers to PLA matrix can significantly improve its crystallization properties and melt elasticity, as well as enhance the foaming behavior of PLA.
CARBOHYDRATE POLYMERS
(2022)
Article
Materials Science, Paper & Wood
Jisuk Lee, Yuta Hikima, Takafumi Sekiguchi, Masahiro Ohshima
Summary: The rheological and thermal properties of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and chemically modified cellulose nanofiber nanocomposites (PHBH/CNF) were studied. The composite material showed improved crystallization rate, viscosity, and mechanical properties compared to pure PHBH. The injection molding process was successfully used to enhance the processability of PHBH.
Article
Polymer Science
Weiyuan Lin, Yuta Hikima, Masahiro Ohshima
Summary: Styrene-isobutylene-styrene copolymer (SIBS) is a thermoplastic elastomer with excellent chemical stability, biocompatibility, and low gas permeability. By introducing polypropylene (PP) in foam injection molding processes, the foamability can be improved and the shrinkage of SIBS foams can be impeded.
JOURNAL OF APPLIED POLYMER SCIENCE
(2022)
Article
Polymer Science
Podchara Rattanakawin, Kenji Yoshimoto, Yuta Hikima, Shinsuke Nagamine, Yuhan Jiang, Masatoshi Tosaka, Shigeru Yamago, Masahiro Ohshima
Summary: A method of fabricating highly ordered nanocellular foam using UV-induced chemical foaming technique and self-assembly of block copolymer PMMA-b-PtBA was reported. Different self-assembled morphologies were investigated for their effects on the formation of nanocellular foams. It was found that cells generated from the lamella templates had higher expandability compared to those from the cylindrical templates. Increasing the molecular weight of PMMA could mitigate the drastic change in cell structure.
Article
Engineering, Chemical
Weiyuan Lin, Yoshiki Hamamoto, Yuta Hikima, Masahiro Ohshima
Summary: This study proposed a method to improve the surface appearance of polypropylene (PP) foams from the perspective of material properties. The method focused on reducing bubble size, delaying polymer solidification, squeezing bubbles at the mold-polymer interface, and redissolving bubbles into the polymer. Experimental results showed that the proposed method effectively improved the surface appearance of the foams.
POLYMER ENGINEERING AND SCIENCE
(2023)
Article
Polymer Science
Jisuk Lee, Kenta Moriyama, Yuta Hikima, Masahiro Ohshima
Summary: Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) foams were prepared using nitrogen as a physical blowing agent. The foam injection molding process and the melt memory effect were used to achieve microcellular foams with small cell size and high cell density. Mechanical properties evaluation showed that a high ductility PHBH foam was obtained at a melting temperature of 150 degrees C.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
