Cellulose nanocrystals as biobased nucleation agents in poly-l-lactide scaffold: Crystallization behavior and mechanical properties

Poly (l-lactic acid) (PLLA) is a promising biomedical polymer material with a wide range of applications. The diverse enantiomeric forms of PLLA provide great opportunities for thermal and mechanical enhancement through stereocomplex formation. The addition of poly (d-lactic acid) (PDLA) as a nucleation agent and the formation of stereocomplex crystallization (SC) have been proven to be an effective method to improve the crystallization and mechanical properties of the PLLA. In this study, PLLA was blended with different amounts of PDLA through a melt blending process and their properties were calculated. The effect of the PDLA on the crystallization behavior, thermal, and mechanical properties of PLLA were investigated systematically by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), polarized optical microscopy (POM), dynamic mechanical analysis (DMA), and tensile test. Based on our findings, SC formed easily when PDLA content was increased, and acts as nucleation sites. Both SC and homo crystals (HC) were observed in the PLLA/PDLA blends. As the content of PDLA increased, the degree of crystallization increased, and the mechanical strength also increased.

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Mechanical properties and degradation studies of poly(mannitol sebacate)/cellulose nanocrystals nanocomposites

RSC Advances ◽

10.1039/c5ra06768e ◽

2015 ◽

Vol 5 (69) ◽

pp. 55879-55891 ◽

Cited By ~ 10

Author(s):

Águeda Sonseca ◽

Oscar Sahuquillo ◽

E. Johan Foster ◽

Enrique Giménez

Keyword(s):

Mechanical Properties ◽

Cellulose Nanocrystals ◽

Sebacic Acid ◽

Temperature Profiles ◽

Degradation Studies

Two pre-polymers with ad-mannitol : sebacic acid 1 : 1 and 1 : 2 ratios respectively were combined with cellulose nanocrystals (CNCs) and crosslinked applying different time–temperature profiles to obtain PMS/CNC nanocomposites with different properties.

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Impact of the processing temperature on the crystallization behavior and mechanical properties of poly[R-3-hydroxybutyrate-co-(R-3-hydroxyvalerate)]

Polymer ◽

10.1016/j.polymer.2021.123987 ◽

2021 ◽

pp. 123987

Author(s):

Julie Bossu ◽

Nicolas Le Moigne ◽

Philippe Dieudonné-George ◽

Loïc Dumazert ◽

Valérie Guillard ◽

...

Keyword(s):

Mechanical Properties ◽

Crystallization Behavior ◽

Processing Temperature

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Research on compatibility and surface of high impact bio-based polyamide

High Performance Polymers ◽

10.1177/09540083211005511 ◽

2021 ◽

pp. 095400832110055

Author(s):

Yang Wang ◽

Yuhui Zhang ◽

Yuhan Xu ◽

Xiucai Liu ◽

Weihong Guo

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Differential Scanning Calorimetry ◽

Crystallization Behavior ◽

High Impact ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Scanning Electron

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.

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Effects of Glycerol and Tween 60 on the Crystallization Behavior, Mechanical Properties, and Microstructure of a Plastic Fat

Crystal Growth & Design ◽

10.1021/cg034136v ◽

2004 ◽

Vol 4 (1) ◽

pp. 161-168 ◽

Cited By ~ 26

Author(s):

Jerrold W. Litwinenko ◽

Anand Pal Singh ◽

Alejandro G. Marangoni

Keyword(s):

Mechanical Properties ◽

Crystallization Behavior ◽

Tween 60 ◽

Plastic Fat

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Crystallization behavior, Al-Ce intermetallic formation, and microstructure refinement of near-eutectic Al–Si alloys by rare-earth element additions

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2020-1111108 ◽

2020 ◽

Vol 111 (11) ◽

pp. 938-952

Author(s):

Bo Chi ◽

Zhiming Shi ◽

Cunquan Wang ◽

Liming Wang ◽

Hao Lian ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Rare Earth ◽

Rare Earth Element ◽

Crystallization Behavior ◽

Earth Element ◽

Microstructural Refinement ◽

Preferential Growth ◽

Intermetallic Formation ◽

The Matrix

Abstract Near-eutectic Al-Si alloys have low strength and high brittleness because of the presence of many eutectic b-Si flakes, needle-like Al-Fe-Si intermetallics, and coarse α-Al grains. This study disclosed the effects of cerium-rich RE (rare earth) element modification on orientation characters of crystals, formation of Al-Ce compounds, and microstructural refinement to improve the microstructure and mechanical properties of the alloys. The RE addition depressed preferential growth along the close-packed and/or sub-closepacked planes and promoted growth along the non-closepacked planes, in which La and other elements were dissolved into needle-like Al11Ce3 phase. When the temperature decreased, Al11Ce3 was preferentially crystallized from the melts and then devitrified by attaching to the surface of β-Al5FeSi needles. Moreover, many small Al11Ce3 particles were precipitated in the matrix and on the Si surface by a T6 heat treatment. Eutectic β-Si phases were constructed into discontinuous networks, short rods, and even particles by RE additions, which were further transformed into fine nodules following the T6 treatment. α-Al grains and primary β-Al5FeSi needles were simultaneously refined. The addition of 1.0 wt.% REs and subsequent T6 treatment yielded the highest tensile strength, elongation, and hardness of the alloy.

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A study on the crystallization behavior and mechanical properties of poly(ethylene terephthalate) induced by chemical degradation nucleation

RSC Advances ◽

10.1039/c7ra06823a ◽

2017 ◽

Vol 7 (59) ◽

pp. 37139-37147 ◽

Cited By ~ 6

Author(s):

Diran Wang ◽

Faliang Luo ◽

Zhiyuan Shen ◽

Xuejian Wu ◽

Yaping Qi

Keyword(s):

Mechanical Properties ◽

Crystallization Behavior ◽

Ethylene Terephthalate ◽

Crystallization Rate ◽

Chemical Degradation ◽

Carboxylate Anion ◽

Nucleate Agent ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene ◽

Pet Crystallization

In order to overcome low crystallization rate of PET, HPN-68L was selected to replace the special nucleate agent of PET to improve PET crystallization for its carboxylate anion structure which usually showed high induced nucleation ability for PET.

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Effect of Functionalized MWCNTs with Surfactant and Coupling Agent on Properties of LDPE/POE Blends

Journal of Elastomers & Plastics ◽

10.1177/0095244311413439 ◽

2011 ◽

Vol 43 (6) ◽

pp. 543-558 ◽

Cited By ~ 1

Author(s):

Z. Chen ◽

S. Chen ◽

J. Zhang

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Tensile Strength ◽

Multiwalled Carbon Nanotubes ◽

Crystallization Behavior ◽

Low Density Polyethylene ◽

Favorable Effect ◽

Low Density ◽

Multiwalled Carbon ◽

Polyolefin Elastomer

The surfactant, sodium dodecylbenzenesulfonate (NaDDBS) and coupling agents, γ-aminopropyltriethoxy sliane (KH550) and isopropyl dioleic(dioctylphosphate) titanate (NDZ101) were used to treat multiwalled carbon nanotubes in this work. The effects of surface modification of multiwalled carbon nanotubes on crystallization behavior, mechanical properties, and electrical properties of low density polyethylene/polyolefin elastomer/multiwalled carbon nanotubes composites were studied. The results showed that NaDDBS, KH550, and NDZ101 had a favorable effect of improving the dispersion of multiwalled carbon nanotubes, but it cannot improve the interfacial interactionbetween multiwalled carbon nanotubes and the matrix. The improvement in dispersion favored the crystallization behavior and mechanical properties. Modified multiwalled carbon nanotubes had a better acceleration nucleation effect than raw multiwalled carbon nanotubes on low density polyethylene/polyolefin elastomer blends at low content (≤1 wt%). The tensile strength of low density polyethylene/polyolefin elastomer/multiwalled carbon nanotubes composites with modified multiwalled carbon nanotubes increased with lower multiwalled carbon nanotubes content (≤1 wt%), and KH550 and NDZ101 led low density polyethylene/polyolefin elastomer/multiwalled carbon nanotubes composites to possess a higher tensile strength than that of NaDDBS with 1 wt% content. NaDDBS, KH550, and NDZ101 had a minor influence on the dielectric properties of the composites and even caused a decrease in the dielectric loss of composites with 10 wt% multiwalled carbon nanotubes content.

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