Mechanical properties and heat resistance of stereocomplex polylactide/copolyester blend films prepared by in situ melt blending followed with compression molding

Ecofriendly poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-b-PEG-b-PLLA) are flexible bioplastics. In this work, the blending of poly(D-lactide)-b-poly(ethylene glycol)-b-poly(D-lactide) (PDLA-b-PEG-b-PDLA) with various blend ratios for stereocomplex formation has been proved to be an effective method for improving the mechanical properties and heat resistance of PLLA-b-PEG-b-PLLA films. The PLLA-b-PEG-b-PLLA/PDLA-b-PEG-b-PLDA blend films were prepared by melt blending followed with compression molding. The stereocomplexation of PLLA and PDLA end-blocks were characterized by differential scanning calorimetry and X-ray diffraction (XRD). The content of stereocomplex crystallites of blend films increased with the PDLA-b-PEG-b-PDLA ratio. From XRD, the blend films exhibited only stereocomplex crystallites. The stress and strain at break of blend films obtained from tensile tests were enhanced by melt blending with the PDLA-b-PEG-b-PDLA. The heat resistance of blend films determined from testing of dimensional stability to heat and dynamic mechanical analysis were improved with the PDLA-b-PEG-b-PDLA ratio. The sterecomplex PLLA-b-PEG-b-PLLA/PDL-b-PEG-b-PDLA films prepared by melt processing could be used as flexible and good heat-resistance packaging bioplastics.

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Influence of Chain-Extension Reaction on Stereocomplexation, Mechanical Properties and Heat Resistance of Compressed Stereocomplex-Polylactide Bioplastic Films

Polymers ◽

10.3390/polym10111218 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1218 ◽

Cited By ~ 5

Author(s):

Yodthong Baimark ◽

Sumet Kittipoom

Keyword(s):

Mechanical Properties ◽

Differential Scanning Calorimetry ◽

Heat Resistance ◽

Tensile Testing ◽

Chain Extender ◽

Chain Extension ◽

Melt Blending ◽

Scanning Calorimetry ◽

X Ray ◽

Xrd Patterns

Stereocomplex polylactide (scPLA) films were prepared by melt blending of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) with and without an epoxy-based chain extender before compression molding. The obtained scPLA films were characterized through differential scanning calorimetry, X-ray diffractometry (XRD), tensile testing and dimensional stability to heat. XRD patterns revealed that all the scPLA films had only stereocomplex crystallites. The obtained results showed that the chain-extension reaction improved mechanical properties of the scPLA films, however, it suppressed stereocomplexation and heat resistance.

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Study on Reactive Blend Systems of PA1010/ABS/PP

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.3146 ◽

2011 ◽

Vol 239-242 ◽

pp. 3146-3149

Author(s):

Jia Min Zhang ◽

Ming Yi Zhu ◽

Zhao Xun Lian

Keyword(s):

Mechanical Properties ◽

Graft Copolymer ◽

Melt Blending ◽

Elongation At Break ◽

Melt Grafting ◽

Blending Process ◽

Reactive Blend ◽

Pp Blends ◽

The Impact

The impacts of multi-monomers melt grafting blends of maleic anhydride(MAH) and Styrene (St) on the crystallization behavior, morphology and mechanical properties of PA1010/ABS/PP blends were studied through the methods of SEM,themal analysis, mechanical properties analysis. The results showed that the graft copolymer generated in situ by the anhydride groups of g-PP and the amino end of PA1010 reduced the interfacial tension of blends efficiently, and the interaction of the styrene groups of the graft copolymer and ABS is helpful to improve the compatibility of three components during the melt blending process. The size of dispersed phase in blends is reduced obviously and the mechanical properties have a great improvement when the percentage of g-PP in the PA1010/ABS/PP blends increases to 10%. The tensile strength of the compatibilized PA1010/ABS/PP blends is improved by 11.7%,and the impact strength and elongation at break are increased 4 times and 4.9 times, respectively.

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In-situ fibrillated polytetrafluoroethylene (PTFE) in thermoplastic polyurethane (TPU) via melt blending: Effect on rheological behavior, mechanical properties, and microcellular foamability

Polymer ◽

10.1016/j.polymer.2017.11.053 ◽

2018 ◽

Vol 134 ◽

pp. 263-274 ◽

Cited By ~ 41

Author(s):

An Huang ◽

Xiangfang Peng ◽

Lih-Sheng Turng

Keyword(s):

Mechanical Properties ◽

Rheological Behavior ◽

Thermoplastic Polyurethane ◽

Melt Blending

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Dynamics of Nanoparticle Chain Aggregates of Carbon Under Tension

MRS Proceedings ◽

10.1557/proc-778-u4.4 ◽

2003 ◽

Vol 778 ◽

Author(s):

Rajdip Bandyopadhyaya ◽

Weizhi Rong ◽

Yong J. Suh ◽

Sheldon K. Friedlander

Keyword(s):

Mechanical Properties ◽

Carbon Black ◽

Polymer Film ◽

Elastic Behavior ◽

Small Strains ◽

Transmission Electron ◽

Chain Aggregates ◽

Nanoparticle Chains ◽

Reinforcing Filler

AbstractCarbon black in the form of nanoparticle chains is used as a reinforcing filler in elastomers. However, the dynamics of the filler particles under tension and their role in the improvement of the mechanical properties of rubber are not well understood. We have studied experimentally the dynamics of isolated nanoparticle chain aggregates (NCAs) of carbon made by laser ablation, and also that of carbon black embedded in a polymer film. In situ studies of stretching and contraction of such chains in the transmission electron microscope (TEM) were conducted under different maximum values of strain. Stretching causes initially folded NCA to reorganize into a straight, taut configuration. Further stretching leads to either plastic deformation and breakage (at 37.4% strain) or to a partial elastic behavior of the chain at small strains (e.g. 2.3% strain). For all cases the chains were very flexible under tension. Similar reorientation and stretching was observed for carbon black chains embedded in a polymer film. Such flexible and elastic nature of NCAs point towards a possible mechanism of reinforcement of rubber by carbon black fillers.

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