scholarly journals Structure-regulated tough elastomer of liquid crystalline inorganic nanosheets/polyurethane nanocomposite

2021 ◽  
Author(s):  
Toki Morooka ◽  
Yutaka Ohsedo ◽  
Riki Kato ◽  
Nobuyoshi Miyamoto

Liquid crystalline nanosheets/polyurethane composite elastomers with superior mechanical properties were successfully synthesized by newly developed in-situ polymerization technique. A layered clay mineral fluorohectorite was fully exfoliated into single-layer nanosheets and...

2014 ◽  
Vol 1015 ◽  
pp. 381-384
Author(s):  
Li Liu ◽  
Li Hai Cai ◽  
Dan Liu ◽  
Jun Xu ◽  
Bao Hua Guo

The poly (butylene succinate) (PBS) and 3 wt% attapulgite (ATP) reinforced PBS/ATP nanocomposites with 1,6-hexanediol were fabricated using an in situ polymerization method. The crystallization behaviors indicated that ATP had effectively acted as nucleating agent, resulting in the enhancement on the crystallization temperature. The SEM results showed a superior interfacial linkage between ATP and PBS. Also, ATP could disperse as a single fiber and embed in the polymer matrix, which resulted in the improved mechanical properties.


2013 ◽  
Vol 750-752 ◽  
pp. 7-10
Author(s):  
Kou An Hao ◽  
Zhen Qing Wang ◽  
Li Min Zhou

Fiber impregnation has been the main obstacle for thermoplastic matrix with high viscosity. This problem could be surmounted by adapting low viscous polymeric precursors Woven basalt fabric reinforced poly (butylenes terephthalate) composites were produced via in-situ polymerization at T=210°C. Before polymerization, catalyst was introduced to the reinforcement surface with different concentration. DSC is used to determine the polymerization and crystallization. SEM is used to detect whether the catalyst existed on surface. Both flexural and short-beam shear test are employed to study the corresponding mechanical properties.


2019 ◽  
Vol 10 (8) ◽  
pp. 1725
Author(s):  
Raffaella Aversa ◽  
Relly Victoria Virgil Petrescu ◽  
Antonio Apicella ◽  
Florian Ion Tiberiu Petrescu

A method for PET mechanical properties enhancement by reactive blending with HBA/HNA Liquid Crystalline Polymers for in situ highly fibrillar composites preparation is presented. LCP/PET blends were reactively extruded in presence of Pyromellitic Di-Anhydride (PMDA) and then characterized by Differential Scanning Calorimetry, Thermally Stimulated Currents and tensile mechanical properties. Moderate amounts of LCP in the PET (0.5 and 5%) and small amounts of thermo-active and reactive compatibilizer in the blend (0.3%) were found to significantly improve LCP melt dispersion, melts shear transfer and LCP fibril formation and adhesion. An unexpected improvement was probably due to the presence of two distinct phases’ supra-molecular structures involving PET-LCP and PMDA.


Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 4 ◽  
Author(s):  
Orsolya Viktória Semperger ◽  
András Suplicz

With the rapid development of the automotive industry, there is also a significant need to improve the raw materials used. Therefore, the demand is increasing for polymer composites with a focus on mass reduction and recyclability. Thermoplastic polymers are preferred because of their recyclability. As the automotive industry requires mass production, they require a thermoplastic raw material that can impregnate the reinforcement in a short cycle time. The most suitable monomer for this purpose is caprolactam. It can be most efficiently processed with T-RTM (thermoplastic resin transfer molding) technology, during which polyamide 6 is produced from the low-viscosity monomer by anionic ring-opening (in situ) polymerization in a tempered mold with a sufficiently short cycle time. Manufacturing parameters, such as polymerization time and mold temperature, highly influence the morphological and mechanical properties of the product. In this paper, the properties of polyamide 6 produced by T-RTM are analyzed as a function of the production parameters. We determine the crystallinity and the residual monomer content of the samples and their effect on mechanical properties.


Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1123 ◽  
Author(s):  
Hui Liang ◽  
Yun Zhao ◽  
Jinjun Yang ◽  
Xiao Li ◽  
Xiaoxian Yang ◽  
...  

The present work focuses on the preparation of poly(l–lactide)–magnesium oxide whiskers (PLLA–MgO) composites by the in-situ polymerization method for bone repair and implant. PLLA–MgO composites were evaluated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and solid-state 13C and 1H nuclear magnetic resonance spectroscopy (NMR). It was found that the whiskers were uniformly dispersed in the PLLA matrix through the interfacial interaction bonding between PLLA and MgO; thereby, the MgO whisker was found to be well-distributed in the PLLA matrix, and biocomposites with excellent interface bonding were produced. Notably, the MgO whisker has an effect on the crystallization behavior and mechanical properties; moreover, the in vivo degradation of PLLA–MgO composites could also be adjusted by MgO. These results show that the whisker content of 0.5 wt % and 1.0 wt % exhibited a prominent nucleation effect for the PLLA matrix, and specifically 1.0 wt % MgO was found to benefit the enhanced mechanical properties greatly. In addition, the improvement of the degrading process of the composite illustrated that the MgO whisker can effectively regulate the degradation of the PLLA matrix as well as raise its bioactivity. Hence, these results demonstrated the promising application of PLLA–MgO composite to serve as a biomedical material for bone-related repair.


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