Morphology and thermal properties of clay based biocomposites

Abstract Carboxymethylcellulose/poly(ethylene glycol) (CMC/PEG) blend and CMC/PEG/montmorillonite (MMT) nanocomposites were produced by the solvent casting method. The clay, a sodium MMT, was incorporated in the polymer matrix at low weight loadings (from 1 wt% to 7 wt%). The MMT dispersion in the matrix was evaluated by X-ray diffraction, which revealed an intercalated structure of the nanocomposites. Different levels of intercalation have been detected. The changes in morphology caused by the addition of layered silicate on CMC/PEG blend were investigated by scanning electron microscopy (SEM). The SEM images of CMC/PEG blend containing 5% of MMT displayed more homogenous morphology than CMC/PEG blend. The compatibilizing performance of the filler was investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectroscopy. The effect of the introduction of the clay on the crystallization temperature, melting temperature and crystallization degree of CMC/PEG revealed that clay behaved as a nucleating agent and enhanced the crystallization rate of PEG. Furthermore, it was demonstrated that the addition of a small percentage of montmorillonite (1%) was enough to improve the thermal stability of the nanocomposites.

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Structure and Performance of PP Porous Membrane Prepared with Adipic Acid and NA-40 as Nucleating Agent via TIPS

Materials Science Forum ◽

10.4028/www.scientific.net/msf.848.733 ◽

2016 ◽

Vol 848 ◽

pp. 733-737

Author(s):

Hui Xia Xuan ◽

Chun Ju He

Keyword(s):

Adipic Acid ◽

Water Flux ◽

Nucleating Agent ◽

Porous Membrane ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Sem Images ◽

Thermally Induced ◽

Cooling Temperature ◽

And Performance

Polypropylene (PP) membranes were respectively prepared using adipic acid (APA) and Sorbitol (NA-40) as nucleating agent via thermally induced phase separation (TIPS) method. The effects of nucleating agent content and cooling temperature on the structure and performance of membrane were investigated using scanning electron microscopy (SEM), wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). WAXD spectrogram indicates that three kinds of α, β and γ-form crystal were formed in this preparation process and the relative content of β-form crystal in membrane prepared by NA-40 system is higher than that of membrane formed by adipic acid. SEM images show that porous structure and cellular structure were observed on the surface and cross-section of membrane. The water flux, tensile strength and elongation increase with the addition of nucleating agent content and decrease with cooling temperature rising. This paper aims to choose proper nucleating agent NA-40 and coagulation temperature to improve the properties of PP membranes.

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Thermal and Nanoindentation Behaviours of Layered Silicate Reinforced Recycled GF-12 Nanocomposites

Journal of Materials Science Research ◽

10.5539/jmsr.v5n4p10 ◽

2016 ◽

Vol 5 (4) ◽

pp. 10

Author(s):

A. Shalwan ◽

A. I. Alateyah ◽

B. Aldousiri ◽

M. Alajmi

Keyword(s):

Layered Silicate ◽

Nucleating Agent ◽

Slight Improvement ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Polyamide 12 ◽

Recycled Glass ◽

Base Polymer ◽

Positive Effect

This work is an attempt to improve the thermal and nanoindentation behaviours of recycled Glass-Filled Polyamide-12 (GF-12) by adding layered Silicate (Nanoclay) as a reinforced filler. Differential Scanning Calorimetry (DSC) and Nanoindentation tests were conducted to study the effect of various loading levels (0-7 wt. %) of Nano-layered silicate on the thermal and nanohardness behaviours of GF-12 and its nanocomposites. Wide Angle X-ray Diffraction (WAXD) was employed to characterise the nanostructure of material and determine the intercalation/exfoliation for layered silicate in a GF-12 matrix. This study reveals that the layer silicate has a positive effect on the hardness results. Nanoindentation results showed remarkable improvement when layered silicate was added to recycled GF-12. The Glass transition (Tg) and crystallization (Tc) temperatures showed a slight improvement over the base polymer by the incorporation of layered silicate. Moreover, the enhancement of crystallization was obvious with the addition of clay loading, which functioned as a nucleating agent that could increase the rate of crystallization.

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Gelation Crystallization of Poly(L-Lactide) in Solvents of Varying Molecular Size

Polymers and Polymer Composites ◽

10.1177/096739110701500506 ◽

2007 ◽

Vol 15 (5) ◽

pp. 389-393

Author(s):

Hong Hao ◽

Guozheng Liang ◽

Junmin Zhao

Keyword(s):

Differential Scanning Calorimetry ◽

Ethylene Glycol ◽

Crystallization Rate ◽

Molecular Size ◽

Large Molecule ◽

X Ray Diffraction ◽

Poly Ethylene Glycol ◽

Scanning Calorimetry ◽

X Ray ◽

Poly Ethylene

The crystallization behaviour of poly(L-lactide) (PLLA) samples prepared in large-molecule solvents, such as poly(ethylene glycol) (PEG), was studied by differential scanning calorimetry (DSC) and X-ray diffraction. The results indicate that those samples recovered from large-molecule solvents exhibit higher crystallinity, non-isothermal crystallization temperature and faster crystallization rate than the ones crystallized in a small-molecule solvent. The crystallinity of samples from PLLA/PEG gel is about 73% measured by the DSC. The molar size of the solvent has a large influence on the formation of helical conformations and, thereby on the crystallization rate of PLLA in solution.

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Effect of Composition on the Crystallization, Water Absorption, and Biodegradation of Poly(ε-caprolactam-co-ε-caprolactone) Copolymers

Polymers ◽

10.3390/polym12112488 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2488

Author(s):

Yuanyuan Dou ◽

Xinyu Mu ◽

Yuting Chen ◽

Zhenbo Ning ◽

Zhihua Gan ◽

...

Keyword(s):

Water Absorption ◽

Crystallization Rate ◽

Nucleating Agent ◽

Melting Behavior ◽

Feed Ratio ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Molar Feed Ratio ◽

Anionic Copolymerization

Poly(ester amide)s have aroused extensive research interest due to the combination of the degradability of polyester and the higher mechanical properties of polyamide. In this work, a series of poly(ε-caprolactam-co-ε-caprolactone) (P(CLA-co-CLO)) copolymers with different compositions were synthesized by anionic copolymerization. The structure, crystallization behavior, water absorption, and biodegradation behavior of these copolymers were investigated by means of nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and polarized optical micrographs (POM). The results indicated that the composition of P(CLA-co-CLO) copolymers can be adjusted by the molar feed ratio. The PCL blocks decreased the crystallization rate of PA6 blocks but had little effect on the melting behavior of PA6, while the crystallized PA6 acted as a heterogeneous nucleating agent and greatly improved the crystallization rate of PCL. Moreover, the introduction of PCL blocks greatly reduced the water absorption of P(CLA-co-CLO) copolymers and endow them a certain degree of degradability.

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The effect of attapulgite on crystallization behavior of Poly(ethylene terephthalate) (PET)/Attapulgite (AT) nano composites

e-Polymers ◽

10.1515/epoly.2007.7.1.1344 ◽

2007 ◽

Vol 7 (1) ◽

Author(s):

Fan Xufen ◽

Chen Dajun

Keyword(s):

Ethylene Terephthalate ◽

In Situ Polymerization ◽

Nucleating Agent ◽

Avrami Equation ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

AbstractPoly (ethylene terephthalate) (PET)/Attapulgite (AT) nanocomposites were prepared via in-situ polymerization. According to the observation of transmission electron microscopy (TEM), attapulgite is well dispersed in the PET matrix in a nanometer scale. The influence of attapulgite content on the nonisothermal crystallization kinetics was studied using a classical Avrami equation with Jeziorny method. The crystalline structures of the pure PET and PET/AT nanocomposites with different amount of AT (0.2%, 0.5%, 1%, 2%) were characterized by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) methods. It was found that the crystallization temperature for PET/AT nanocomposites with 0.2% and 0.5% content of AT were higher than pure PET and the rate of crystallization of all PET/AT nanocomposite samples increased significantly which indicated that attapulgite could be used as an effective nucleating agent in PET. However, with the addition of AT, smaller crystalline size, more crystalline defects and lower degree of crystallization was demonstrated.

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Preparation of poly(L-lactide)/poly(ethylene glycol)/organo-modified montmorillonite nanocomposites via melt intercalation under continuous elongation flow

Journal of Polymer Engineering ◽

10.1515/polyeng-2017-0229 ◽

2018 ◽

Vol 38 (5) ◽

pp. 449-460 ◽

Cited By ~ 2

Author(s):

Ting Wu ◽

Ding Yuan ◽

Jin-Ping Qu

Keyword(s):

Thermal Stability ◽

Ethylene Glycol ◽

Crystallization Rate ◽

Nucleating Agent ◽

Nucleation Density ◽

Poly Ethylene Glycol ◽

Scanning Calorimetry ◽

Modified Montmorillonite ◽

Elongation Flow ◽

Poly Ethylene

AbstractAn innovative eccentric rotor extruder (ERE), which can generate continuous elongation flow, was used to prepare the poly(L-lactide) (PLLA)/poly(ethylene glycol) (PEG)/organo-modified montmorillonite (OMMT) nanocomposites. The morphology was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and showed that the OMMT nanoparticles were uniformly dispersed in the matrix and mainly existed in intercalation mode. The influence of OMMT on the rheological behavior of plasticized PLLA was investigated by dynamic rheological measurements, showing greater improvement of rheological properties compared to that of PLLA/PEG blend. The crystallization behavior and crystalline structures were studied by differential scanning calorimetry (DSC) and XRD, respectively, and showed that the presence of OMMT further speeds up the crystallization rate of plasticized PLLA. However, the crystallization rate and crystallinity had a slight downward trend at high OMMT content because of the inhibition effect of the OMMT percolation network structure. Polarizing optical microscopy (POM) was further carried out and proved that the OMMT nanoparticles as a heterogeneous nucleating agent can increase the spherulite growth rate and nucleation density. The thermal stability was investigated by thermogravimetric analysis and indicated that the addition of OMMT at low concentration can improve the thermal stability of plasticized PLLA more effectively.

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Preparation and characterization of poly(3-hydroxybutyrate)/ Cloisite25A nanocomposites

e-Polymers ◽

10.1515/epoly-2013-0125 ◽

2013 ◽

Vol 13 (1) ◽

Author(s):

Matko Erceg ◽

Dražan Jozić

Keyword(s):

Crystallization Rate ◽

Nucleating Agent ◽

Degree Of Crystallinity ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Tg Analysis ◽

Solution Intercalation ◽

X Ray ◽

Thermal Stability Of

Abstract Poly(3-hydroxybutyrate)/Cloisite25A (PHB/25A) nanocomposites were prepared by solution-intercalation method. The intercalation of PHB chains between the layers of Cloisite25A was observed by X-ray diffraction (XRD). Differential scanning calorimetry (DSC) and non-isothermal thermogravimetry (TG) analysis were performed to study the thermal properties, crystallization and the thermal degradation of the prepared nanocomposites. DSC analysis indicates that Cloisite25A acts as a nucleating agent and increases the crystallization rate of PHB, but due to intercalation reduces its overall degree of crystallinity. TG analysis shows that addition of Cloisite25A enhances the thermal stability of PHB.

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Effect of thermally stable oligomerically modified clay on the properties of aramid-based nanocomposite materials

Journal of Materials Research ◽

10.1557/jmr.2008.0406 ◽

2008 ◽

Vol 23 (12) ◽

pp. 3330-3338 ◽

Cited By ~ 4

Author(s):

Sonia Zulfiqar ◽

Muhammad Ilyas Sarwar

Keyword(s):

Water Absorption ◽

Composite Films ◽

Layered Silicate ◽

Clay Content ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Carbonyl Chloride ◽

The Matrix ◽

Absorption Measurements

Oligomerically modified reactive montmorillonite clay was used in the preparation of aramid-layered silicate nanocomposites. The dispersion behavior of organoclay was monitored in the aramid matrix synthesized from 4-aminophenylsulfone and isophthaloyl chloride in dimethylacetamide. These polyamide chains were end-capped with carbonyl chloride groups to interact chemically with oligomerically modified layered silicate. Thin composite films containing 2 to 20 wt% of organoclay were probed for x-ray diffraction (XRD), transmission electron microscopy (TEM), mechanical testing, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and water absorption measurements. XRD and TEM results described the distribution level of clay platelets and morphology of hybrid materials. Mechanical measurements revealed that modulus and strength improved up to 6 wt% clay loading, while toughness of nanocomposites increased with the addition of 2 wt% clay content in the matrix. The elongation showed a decreasing trend with increasing clay content in the hybrids. Thermal-decomposition temperatures of the nanocomposites were in the range 225 to 450 °C. The glass-transition temperature increased up to 12 wt% addition of organoclay in the matrix relative to pristine aramid depicting interfacial interactions among the phases. Water absorption of the nanocomposites reduced with augmenting organoclay loading, indicating decreased permeability.

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Comparative study of the effect of TiO2 and ZnO on the crystallization of PHB

Matéria (Rio de Janeiro) ◽

10.1590/s1517-707620170004.0214 ◽

2017 ◽

Vol 22 (4) ◽

Cited By ~ 5

Author(s):

Nichollas Guimarães Jaques ◽

Ingridy Dayane dos Santos Silva ◽

Manoel da Cruz Barbosa Neto ◽

Rayane Karoline Melo Diniz ◽

Renate Maria Ramos Wellen ◽

...

Keyword(s):

Crystallization Rate ◽

Nucleating Agent ◽

Scanning Calorimetry ◽

Sem Images ◽

Dsc Studies ◽

Heating And Cooling ◽

Internal Mixer ◽

Zno And Tio2 Nanoparticles ◽

Fractured Surface ◽

Scanning Electron

ABSTRACT PHB/TiO2 and PHB/ZnO compounds were prepared in a laboratory internal mixer. Crystallization was investigated by differential scanning calorimetry (DSC) with heating and cooling rates ranging from 5 to 30 °C/min. Fractured surface of selected samples was analysed by scanning electron microscopy (SEM). From the SEM images, it was observed that ZnO and TiO2 nanoparticles were properly dispersed in the PHB matrix. DSC studies revealed that the addition of TiO2 and ZnO changed the temperature and crystallization rate but did not affect the total crystallinity significantly. In general, TiO2 behaved as nucleating agent greatly influencing the PHB crystallization.

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Poly(δ-valerolactone)/Poly(ethylene-co-vinylalcohol)/β-Tricalcium Phosphate Composite as Scaffolds: Preparation, Properties, and In Vitro Amoxicillin Release

Polymers ◽

10.3390/polym13010046 ◽

2020 ◽

Vol 13 (1) ◽

pp. 46

Author(s):

Mohammed Badwelan ◽

Mohammed Alkindi ◽

Osama Alghamdi ◽

Waseem Sharaf Saeed ◽

Abdel-Basit Al-Odayni ◽

...

Keyword(s):

Hybrid Materials ◽

Tricalcium Phosphate ◽

Drug Carrier ◽

Human Mesenchymal Stem Cells ◽

In Vitro Study ◽

Micro Computed Tomography ◽

Scanning Calorimetry ◽

Sem Images ◽

Poly Ethylene

Two poly(δ-valerolactone)/poly(ethylene-co-vinylalcohol)/β-tricalcium phosphate (PEVAL/PDVAL/β-TCP) composites containing an equal ratio of polymer and filled with 50 and 70 wt% of β-TCP microparticles were prepared by the solvent casting method. Interconnected pores were realized using the salt leached technique, and the porosity of the resulted composites was evaluated by the scanning electron microscopy (SEM) method. The homogeneity of the hybrid materials was investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis. The prepared materials’ SEM images showed interconnected micropores that respond to the conditions required to allow their uses as scaffolds. The porosity of each scaffold was determined from micro computed tomography (micro-CT) data, and the analysis of the mechanical properties of the prepared materials was studied through the stress-strain compressive test. The proliferation test results used human mesenchymal stem cells (MSCs) to grow and proliferate on the different types of prepared materials, reflecting that the hybrid materials were non-toxic and could be biologically acceptable scaffolds. The antibacterial activity test revealed that incorporation of amoxicillin in the specimens could inhibit the bacterial growth of S. aureus. The in vitro study of the release of amoxicillin from the PEVAL/PDVAL/amoxicillin and PEVAL/PDVAL/β-TCP/amoxicillin drug carrier systems in pH media 7.4, during eight days, gave promising results, and the antibiotic diffusion in these scaffolds obeys the Fickian model.

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