Ultrafine dispersion of a phosphate nucleating agent in a polypropylene matrix via the microemulsion method

Propylene-based random copolymers with either ethylene or 1-hexene as comonomer, produced using a metallocene catalyst, were studied regarding their crystallization behaviors, with a focus on rapid cooling. To get an impression of processing effects, fast scanning chip calorimetry (FSC) was used in addition to the characterization of the mechanical performance. When comparing the comonomer type and the relation to commercial grades based on Ziegler–Natta-type catalysts, both an interaction with the catalyst-related regio-defects and a significant difference between ethylene and 1-hexene was observed. A soluble-type nucleating agent was found to modify the behavior, but to an increasingly lesser degree at high cooling rates.

Download Full-text

Influence of active nanofiller ZIF-8 metal-organic framework (MOF) by microemulsion method on anticorrosion of epoxy coatings

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2021.126836 ◽

2021 ◽

pp. 126836

Author(s):

Song Duan ◽

Baojie Dou ◽

Xiuzhou Lin ◽

Shixiong Zhao ◽

Wilfred Emori ◽

...

Keyword(s):

Metal Organic Framework ◽

Epoxy Coatings ◽

Microemulsion Method ◽

Metal Organic ◽

Organic Framework

Download Full-text

Effect of stearic acid treatment on the properties of aligned short hemp fibre mats and their potential use as reinforcement in polypropylene matrix composites

Cellulose ◽

10.1007/s10570-021-03884-w ◽

2021 ◽

Author(s):

Kim L. Pickering ◽

Tom Sunny

Keyword(s):

Stearic Acid ◽

Acid Treatment ◽

Matrix Composites ◽

Hemp Fibre ◽

Polypropylene Matrix ◽

Potential Use

Download Full-text

Fabrication and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite

e-Polymers ◽

10.1515/epoly-2021-0006 ◽

2020 ◽

Vol 21 (1) ◽

pp. 038-046

Author(s):

Xu Yan ◽

Wanru Zhou ◽

Xiaojun Ma ◽

Binqing Sun

Keyword(s):

Thermal Stability ◽

Oxygen Permeability ◽

Water Vapor Permeability ◽

Barrier Properties ◽

Nucleating Agent ◽

Vapor Permeability ◽

Casting Method ◽

Increasing Trend ◽

Solution Casting Method

Abstract In this study, a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite (MMT/PHBH) was fabricated by solution-casting method. The results showed that the addition of MMT increased the crystallinity and the number of spherulites, which indicated that MMT was an effective nucleating agent for PHBH. The maximum decomposition peak of the biocomposites moved to a high temperature and residue presented an increasing trend. The biocomposites showed the best thermal stability at 1 wt% MMT. Compared with PHBH, 182.5% and 111.2% improvement in elastic modulus and tensile strength were obtained, respectively. Moreover, the oxygen permeability coefficient and the water vapor permeability of MMT/PHBH biocomposites decreased by 43.9% and 6.9%, respectively. It was also found that the simultaneous enhancements on the crystallizing, thermal stability, mechanical, and barrier properties of biocomposites were mainly caused by the formation of intercalated structure between PHBH and MMT.

Download Full-text

Synthesis and characterization of surfactant assisted hydroxyapatite powder using microemulsion method

Materials Today Proceedings ◽

10.1016/j.matpr.2021.05.059 ◽

2021 ◽

Author(s):

V. Collins Arun Prakash ◽

I. Venda ◽

V. Thamizharasi

Keyword(s):

Synthesis And Characterization ◽

Microemulsion Method ◽

Hydroxyapatite Powder ◽

Surfactant Assisted

Download Full-text

Effect of C-S-H Nucleating Agent on Cement Hydration

Applied Sciences ◽

10.3390/app11146638 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6638

Author(s):

Wenhao Zhao ◽

Xuping Ji ◽

Yaqing Jiang ◽

Tinghong Pan

Keyword(s):

Fractal Dimension ◽

Cement Hydration ◽

Nucleating Agent ◽

Crystal Nucleation ◽

Enhancement Effect ◽

Hydration Products ◽

Hydration Degree ◽

Hydration Kinetics ◽

Cement Mortars ◽

Early Strength

This work aims to study the effect of a nucleating agent on cement hydration. Firstly, the C-S-H crystal nucleation early strength agent (CNA) is prepared. Then, the effects of CNA on cement hydration mechanism, early strength enhancement effect, C-S-H content, 28-days hydration degree and 28-days fractal dimension of hydration products are studied by hydration kinetics calculation, resistivity test, BET specific surface area test and quantitative analysis of backscattered electron (BSE) images, respectively. The results show that CNA significantly improves the hydration degree of cement mixture, which is better than triethanolamine (TEA). CNA shortens the beginning time of the induction period by 49.3 min and the end time of the cement hydration acceleration period by 105.1 min than the blank sample. CNA increases the fractal dimension of hydration products, while TEA decreases the fractal dimension. CNA significantly improves the early strength of cement mortars; the 1-day and 3-days strength of cement mortars with CNA are more than the 3-days and 7-days strength of the blank sample. These results will provide a reference for the practical application of the C-S-H nucleating agent.

Download Full-text