Polyurethane/clay nanocomposites with improved helium gas barrier and mechanical properties: Direct versus master-batch melt mixing route

2018 ◽  
Vol 135 (27) ◽  
pp. 46422 ◽  
Author(s):  
Bapan Adak ◽  
Mangala Joshi ◽  
Bhupendra Singh Butola
2013 ◽  
Vol 844 ◽  
pp. 247-250
Author(s):  
Piriyapol Yokkhun ◽  
Bencha Thongnuanchan ◽  
Charoen Nakason

Nanocomposites based on epoxidized natural rubbers (ENRs) with various levels of epoxide groups (i.e., 10, 20, 30, 40 and 50 mol%) and organoclay were prepared by melt mixing process. The organoclay employed in this study was montmorillonite clay modified by octadecylamine (OC-MMT). Cure characteristics, dynamic properties and mechanical properties of ENRs nanocomposites filled with 5 phr of OC-MMT were studied. In all cases, X-ray diffraction results indicated intercalation of ENRs into the silicate interlayer as an increase in the interlayer distance of layered silicates was observed. The maximum torque and torque difference of ENRs nanocomposites increased with increasing levels of epoxide groups in ENRs. Additionally, it was also found that the tan δ value at Tg of the ENR-50 nanocomposite was much lower than those of other types of ENRs nanocomposite. This indicates stronger interaction between ENR-50 and OC-MMT. However, ENR-50 nanocomposite showed the poorest elasticity in term of the tan δ value at the ambient temperature compared to other types of ENRs nanocomposites. A good balance between strength and elasticity was also observed in the ENR-30 nanocomposite. These results are also consistent with the observation that tensile strength and elongation at break of ENR-30 nanocomposite were higher than those of other types of ENRs nanocomposites.


2011 ◽  
Vol 31 (4) ◽  
Author(s):  
Debdatta Ratna

Abstract In recent years, poly(ethylene oxide) (PEO) has gained two very important applications namely: 1) as solid polymer electrolytes for use in battery, supercapacitor and fuel cell, 2) as a crystallizable switching segment for shape memory polymer (SMP) systems. The common problem for all the applications is linked with the poor mechanical properties of PEO. Hence nanoreinforcement of PEO has been investigated to develop PEO based materials suitable for various applications. PEO/clay nanocomposites have been made by using a solution intercalation method or a melt mixing route. The nanocomposites were characterized by X-ray diffraction (XRD) and evaluated for their rheological and dynamic mechanical properties, Since PEO is sensitive to thermo-oxidative degradations, the effect of processing temperature on rheological properties was also investigated. The detailed processing and characterization of PEO/clay nanocomposites will be discussed in the present paper.


1993 ◽  
Vol 58 (11) ◽  
pp. 2642-2650 ◽  
Author(s):  
Zdeněk Kruliš ◽  
Ivan Fortelný ◽  
Josef Kovář

The effect of dynamic curing of PP/EPDM blends with sulfur and thiuram disulfide systems on their mechanical properties was studied. The results were interpreted using the knowledge of the formation of phase structure in the blends during their melt mixing. It was shown, that a sufficiently slow curing reaction is necessary if a high impact strength is to be obtained. Only in such case, a fine and homogeneous dispersion of elastomer can be formed, which is the necessary condition for high impact strength of the blend. Using an inhibitor of curing in the system and a one-step method of dynamic curing leads to an increase in impact strength of blends. From the comparison of shear modulus and impact strength values, it follows that, at the stiffness, the dynamically cured blends have higher impact strength than the uncured ones.


2014 ◽  
Vol 1025-1026 ◽  
pp. 215-220 ◽  
Author(s):  
Sasirada Weerasunthorn ◽  
Pranut Potiyaraj

Fumed silica particles (SiO2) were directly added into poly (butylene succinate) (PBS) by melt mixing process. The effects of amount of fumed silica particles on mechanical properties of PBS/fumed silica composites, those are tensile strength, tensile modulus, impact strength as well as flexural strength, were investigated. It was found that the mechanical properties decreased with increasing fumed silica loading (0-3 wt%). In order to increase polymer-filler interaction, fumed silica was treated with 3-glycidyloxypropyl trimethoxysilane (GPMS), and its structure was analyzed by FT-IR spectrophotometry. The PBS/modified was found to possess better tensile strength, tensile modulus, impact strength and flexural strength that those of PBS/fumed silica composites.


Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1502
Author(s):  
Eliezer Velásquez ◽  
Sebastián Espinoza ◽  
Ximena Valenzuela ◽  
Luan Garrido ◽  
María José Galotto ◽  
...  

The deterioration of the physical–mechanical properties and loss of the chemical safety of plastics after consumption are topics of concern for food packaging applications. Incorporating nanoclays is an alternative to improve the performance of recycled plastics. However, properties and overall migration from polymer/clay nanocomposites to food require to be evaluated case-by-case. This work aimed to investigate the effect of organic modifier types of clays on the structural, thermal and mechanical properties and the overall migration of nanocomposites based on 50/50 virgin and recycled post-consumer polypropylene blend (VPP/RPP) and organoclays for food packaging applications. The clay with the most hydrophobic organic modifier caused higher thermal stability of the nanocomposites and greater intercalation of polypropylene between clay mineral layers but increased the overall migration to a fatty food simulant. This migration value was higher from the 50/50 VPP/RPP film than from VPP. Nonetheless, clays reduced the migration and even more when the clay had greater hydrophilicity because of lower interactions between the nanocomposite and the fatty simulant. Conversely, nanocomposites and VPP/RPP control films exhibited low migration values in the acid and non-acid food simulants. Regarding tensile parameters, elongation at break values of PP film significantly increased with RPP addition, but the incorporation of organoclays reduced its ductility to values closer to the VPP.


2021 ◽  
Vol 5 (2) ◽  
pp. 48
Author(s):  
Yuxuan Wang ◽  
Yuke Zhong ◽  
Qifeng Shi ◽  
Sen Guo

Thermoplastic starch/butyl glycol ester copolymer/polylactic acid (TPS/PBSA/PLA) biodegradable composites were prepared by melt-mixing. The structure, microstructure, mechanical properties and heat resistance of the TPS/PBSA/PLA composites were studied by Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), tensile test and thermogravimetry tests, respectively. The results showed that PBSA or PLA could bind to TPS by hydrogen bonding. SEM analysis showed that the composite represents an excellent dispersion and satisfied two-phase compatibility when the PLA, TPS and PBSA blended by a mass ration of 10, 30, and 60. The mechanical properties and the heat resistance of TPS/PBSA/PLA composite were improved by adding PLA with content less than 10%, according to the testing results.


2006 ◽  
Vol 39 (2) ◽  
pp. 747-754 ◽  
Author(s):  
Biqiong Chen ◽  
Julian R. G. Evans

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