Article
Chemistry, Multidisciplinary
Enrico Carmeli, Sara Ottonello, Bao Wang, Alfred Menyhard, Alejandro J. Muller, Dario Cavallo
Summary: A more quantitative method to study the efficiency of nucleating agents promoting polypropylene beta-phase is reported in this study. The findings show that the nucleating efficiency scale for alpha-phase is DCHT > TATA > QQ, while for beta-phase it is DCHT > QQ.
Article
Polymer Science
Liyuan Liu, Ying Zhao, Chunbo Zhang, Zhiyuan Dong, Kezhi Wang, Dujin Wang
Summary: The research investigated the impact of the morphological characteristics of N,N'-dicyclohexylterephthalamide (DCHT) on the polymorphic composition of isotactic polypropylene (iPP), showing that small-sized DCHT crystals have a greater influence on the formation of beta-crystals.
Article
Polymer Science
Yang Yue, Xuan Sha, Fushan Wang, Yan Gao, Liangliang Zhang, Xinxin Wang, Jiachun Feng
Summary: The effect of beta-nucleating agent on the self-nucleation of isotactic polypropylene was systematically investigated in this study. It was found that the presence of beta-NA increased the transition temperatures and narrowed the temperature width of the self-nucleation domain of iPP. The increased thermal stability of ordered structures in iPP containing beta-NA may be related to the beta-alpha transformation occurred upon heating.
Article
Polymer Science
Wanxin Peng, Jian Kang, Xiuduo Song, Yue Zhang, Bo Hu, Ya Cao, Ming Xiang
Summary: The effects of MXene on the crystallization behavior of beta-nucleated isotactic polypropylene (iPP) were studied, revealing that the beta-nucleation efficiency of WBG-II is higher than the alpha-nucleation efficiency of MXene when compounded together, indicating a competitive relationship between the two.
Article
Polymer Science
Xian Zhang, Shicheng Zhao, Shiao-Wei Kuo, Wei-Cheng Chen, Mohamed Gamal Mohamed, Zhong Xin
Summary: The study synthesized zinc bicyclo [2.2.1]-heptane-2, 3-dicarboxylate-double-decker silsesquioxanes (Zn2(DDSQ-ND)) for the first time and investigated its effect as a novel and effective nucleating agent in the crystallization behavior of isotactic polypropylene (iPP). The results showed that Zn2(DDSQ-ND) accelerated the formation of ?-phase iPP and acted as a novel ?-nucleating agent in the iPP system.
Article
Polymer Science
Hui Li, Yue-Fei Zhang, Yan Li, Jinrong Zhong
Summary: The study showed that esterified lignin metal salts can serve as effective nucleating agents for isotactic polypropylene (iPP), resulting in increased crystallization temperature and improved toughness. Among them, EL-Zn exhibited strong beta-crystal induction ability to iPP, with potential applications in enhancing the mechanical properties of iPP composites.
JOURNAL OF POLYMER RESEARCH
(2021)
Article
Thermodynamics
Flora Horvath, Dominika Bodrogi, Bendeguz Hilt, Emese Pregi, Alfred Menyhard
Summary: This work presents the nucleation efficiency and special supermolecular structure formed in the presence of novel nucleating agents in isotactic polypropylene. The results show that these nucleating agents are partially soluble in iPP melt and possess dual nucleating ability. The formation of beta-phase is confirmed by calorimetric and thermo-optical measurements. These nucleating agents are the first organogelators with beta-nucleating efficiency.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Materials Science, Multidisciplinary
Yang Yue, Xinxin Wang, Jiachun Feng
Summary: The concentration of nucleating agent DCHT significantly influences the crystallization behavior of iPP, with lower concentrations leading to increased Tc after shearing and decreased Tc after relaxation, while higher concentrations show minimal changes in Tc. Various forms of DCHT and their assembly play a crucial role in the shear-induced crystallization process of iPP.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Engineering, Chemical
Wenjian Shi, Yong Xu, Jun Qin, Xing Li, Qing Lv, Xiaolang Chen, Jie Yu, Mengyu Chen
Summary: In this study, the researchers investigated the effects of calcium sulfate whisker (CSW) and ultrasonically-modified CSW (UCSW) on the crystal structure and isothermal crystallization of isotactic polypropylene (iPP). The results showed that UCSW significantly increased heterogeneous nucleation, decreased overall crystallization time, increased crystallization rate, and reduced crystal size. The addition of UCSW also resulted in a lower apparent equilibrium temperature and an increased content of beta-crystal in the iPP composites.
POLYMER ENGINEERING AND SCIENCE
(2022)
Article
Polymer Science
Juan Li, Chunping Yang, Nan Liu, Shengbao He, Tianwei Sun, Jing Zhang
Summary: A ternary hybrid nucleating agent (THNA) powder was successfully prepared by co-spray drying, which effectively increased the crystallization temperature and improved the mechanical properties and transparency of iPP.
Article
Thermodynamics
Sheng Nie, Jin-Rong Zhong, Yan Li, Yue-Fei Zhang
Summary: A series of polyacrylic salts were investigated as nucleating agents in isotactic polypropylene, and it was found that zinc polyacrylate, potassium polyacrylate, and sodium polyacrylate can induce beta-crystals and improve the impact strength of iPP, while having no significant effect on its tensile strength and flexural modulus.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Polymer Science
Wenxia Jia, Ranran Zhuo, Mingkun Xu, Jiaxiang Lin, Xiaoting Li, Chuntai Liu, Changyu Shen, Chunguang Shao
Summary: Using a homemade pressure device, the synergistic effect of pressurization rate and beta-form nucleating agent on the crystallization of isotactic polypropylene melt was explored. Different crystal phases of iPP were found to be influenced by the pressurization rate, with a competitive growth between beta- and gamma-iPP observed at specific rates. The presence of mesophase was also determined by the pressurization rate, with a theoretical model of pressurization-induced crystallization established to explain the process.
Article
Polymer Science
Junfang Shen, Derong Zhu, Junchao An, Zhiyu Min, Jingbo Chen
Summary: The ordered structure of partially melted iPP was studied using POM and SAXS/WAXS measurements, showing that the surviving ordered structure could relocate and grow into cylindrical nanocrystals. The memory effect of melt was observed during quiescent crystallization from the partially melted sample, indicating a significant influence on crystallization morphology and kinetics.
Article
Thermodynamics
Xiang Wu, Zhengxin Li, Xinjie Dai, Yan Li, Jin-Rong Zhong, Jinlin Tan, Cui-Hong Lu, Yue-Fei Zhang
Summary: The study focuses on the development of high-performance and low-cost composite nucleating agents for isotactic polypropylene (iPP). The addition of nucleated mineral-reinforced compositions significantly enhances the crystallization temperature and improves the mechanical properties of iPP through the synergistic effect of the composite nucleating agent and inorganic fillers.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Polymer Science
W. H. Bednarek, D. Paukszta, M. Szostak, J. Szymanska
Summary: This study analyzed the shear-induced crystallization phenomenon using the in situ POM-shear stage methodology. It found that secondary nucleation plays a greater role in overall crystallization kinetics than shear induced primary nucleation in well-known temperature regimes. The study also concluded that temperature is a key parameter in primary and secondary nucleation process and beta-phase formation in iPP melts.
JOURNAL OF POLYMER RESEARCH
(2021)