Physico-mechanical characterization and biodegradability behavior of polypropylene/poly(L-lactide) polymer blends

Abstract Partially biodegradable polymer films from the blends of polypropylene (PP) and poly(L-lactide) (PLLA) were prepared in an internal mixer by melt blending technique, with and without compatibilizer, maleic anhydride grafted polypropylene (MAPP), followed by compression molding. With regard to tensile properties, 80/20 (PP/PLLA) and 80/20/6 (PP/PLLA/MAPP) were found as the optimum blends with best combination of the ingredients. Therefore, the blend samples, namely, PP80 (80% PP+20% PLLA) and PP80C6 (80% PP+20% PLLA+6 phr MAPP) were selected as ‘optimized’ blends and further characterized for their physical, chemical, morphological, and thermal properties. X-ray diffraction studies showed that neat PP and PP80C6 had the same crystallite size indicating compatibility between PP and PLLA due to MAPP. Fourier transform infrared spectroscopy and scanning electron microsopy investigations revealed that the two polymers were completely immiscible in absence of the compatibilizer. Bacterial biodegradation of the samples was performed by exposure to Pseudomonas stutzeri for 60 days and measured in terms of weight loss, optical density, and thermal stability of the samples before and after degradation. The results showed that 80/20 (PP/PLLA) blends undergo considerable degradation. Reduction in thermal stability of the film samples was also observed through thermogravimetric analysis, which was useful in accelerating their biodegradation.

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Plasticizer effect on melt blending of polylactide stereocomplex

e-Polymers ◽

10.1515/epoly-2016-0331 ◽

2017 ◽

Vol 17 (5) ◽

pp. 409-416 ◽

Cited By ~ 3

Author(s):

Yottha Srithep ◽

Dutchanee Pholharn

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Crystallization Rate ◽

Wide Angle ◽

Melt Blending ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Neat Plla ◽

Internal Mixer

AbstractPoly(l-lactide) (PLLA)/poly(d-lactide) (50/50) with plasticizer contents ranging from 2% to 16% w/w were prepared by melt blending using an internal mixer. Wide-angle X-ray diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetry results confirmed that complete stereocomplex polylactide crystallites without any homocrystallites were produced. Compared to neat PLLA, the melting temperature of the stereocomplex polylactide and its plasticized samples was approximately 55°C higher. Higher plasticizer contents decreased glass transition temperature of the stereocomplex, which implied higher flexibility and enhanced the crystallization rate. However, the plasticizer in the stereocomplex reduced the thermal stability.

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Organo-montimorillonites containing a reactive thiophene group for polythiophenes nanocomposites

Cerâmica ◽

10.1590/0366-69132016623621965 ◽

2016 ◽

Vol 62 (362) ◽

pp. 133-139

Author(s):

J. C. Macêdo-Fonsêca ◽

A. A. A. Tino ◽

M. P. A. Silva-Alves ◽

R. M. Souto-Maior

Keyword(s):

Thermal Stability ◽

Fourier Transform ◽

Montmorillonite Clay ◽

Polymerization Reaction ◽

Ammonium Bromide ◽

X Ray Diffraction ◽

X Ray ◽

Before And After ◽

Thermal Stability Of

Abstract A sodium montmorillonite clay (Na+MMT) was modified with different contents of a reactive salt derived from thiophene (trimethyl-(2-thiophen-3-yl-ethyl)-ammonium bromide) (TMETA). The thiophene salt in the organoclay (xtioMMT) was oxidatively polymerized in situ, giving rise to montmorillonite clay intercalated with a polythiophene salt (xpoltioMMT). Analysis by Fourier transform infrared spectroscopy shows a difference in organization of the salt inside the clay lamellae, before and after its polymerization. X-ray diffraction indicates that the salts, whether polymeric or not, are arranged as a monolayer for all compositions. Differently to the expected, the thermal stability of the organoclays decreases upon polymerization suggesting degradation of TMETA in the polymerization reaction.

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Thermal treatment of magnetite nanoparticles

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.6.143 ◽

2015 ◽

Vol 6 ◽

pp. 1385-1396 ◽

Cited By ~ 27

Author(s):

Beata Kalska-Szostko ◽

Urszula Wykowska ◽

Dariusz Satula ◽

Per Nordblad

Keyword(s):

Thermal Stability ◽

Thermal Treatment ◽

Magnetite Nanoparticles ◽

Surface Characteristics ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Transmission Electron ◽

Before And After ◽

Thermal Stability Of

This paper presents the results of a thermal treatment process for magnetite nanoparticles in the temperature range of 50–500 °C. The tested magnetite nanoparticles were synthesized using three different methods that resulted in nanoparticles with different surface characteristics and crystallinity, which in turn, was reflected in their thermal durability. The particles were obtained by coprecipitation from Fe chlorides and decomposition of an Fe(acac)3 complex with and without a core–shell structure. Three types of ferrite nanoparticles were produced and their thermal stability properties were compared. In this study, two sets of unmodified magnetite nanoparticles were used where crystallinity was as determinant of the series. For the third type of particles, a Ag shell was added. By comparing the coated and uncoated particles, the influence of the metallic layer on the thermal stability of the nanoparticles was tested. Before and after heat treatment, the nanoparticles were examined using transmission electron microscopy, IR spectroscopy, differential scanning calorimetry, X-ray diffraction and Mössbauer spectroscopy. Based on the obtained results, it was observed that the fabrication methods determine, to some extent, the sensitivity of the nanoparticles to external factors.

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Formation and Thermal Stability of Nd0.32Y0.68Si1.7 Layers Formed by Channeled Ion Beam Synthesis

MRS Proceedings ◽

10.1557/proc-514-191 ◽

1998 ◽

Vol 514 ◽

Cited By ~ 1

Author(s):

M. F. Wu ◽

A. Vantomne ◽

S. Hogg ◽

H. Pattyn ◽

G. Langouche ◽

...

Keyword(s):

Thermal Stability ◽

Ion Beam ◽

Hexagonal Structure ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Good Crystalline Quality ◽

Ion Beam Synthesis ◽

Thermal Stability Of

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.

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Study of Thermal Behaviour of EPDM/SBR Blends and Carbon Nanocoatings Deposited by Sputtering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.875.116 ◽

2021 ◽

Vol 875 ◽

pp. 116-120

Author(s):

Muhammad Alamgir ◽

Faizan Ali Ghauri ◽

Waheed Qamar Khan ◽

Sajawal Rasheed ◽

Muhammad Sarfraz Nawaz ◽

...

Keyword(s):

Thermal Stability ◽

Weight Loss ◽

Thermogravimetric Analysis ◽

Thermal Behavior ◽

Thermal Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Stability Of

In this study, the effect of SBR concentration (10 Phr, 20 Phr & 30 Phr ) on the thermal behavior of EPDM/SBR blends was studied. Thermogravimetric analysis (TGA) was used to check weight loss of samples as function of temperature by heating upto 600°C. X-ray diffraction (XRD) was performed to determine quality and % crystallinity of the elastomer blends. It was seen that % crystallinity improved with an increase in the content of SBR in EPDM/SBR blends. TGA revealed that the thermal stability of EPDM/SBR blends has improved by 17% than neat EPDM. Carbon nano-coatings produced by sputtering have no beneficial influence on thermal behaviour of elastomers.

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Syntheses, Crystal Structures and Thermal Stability of Co(II) and Zn(II) Complexes with Ethyl Carbazate

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-0505 ◽

2005 ◽

Vol 60 (5) ◽

pp. 505-510 ◽

Cited By ~ 12

Author(s):

Tong-Lai Zhang ◽

Jiang-Chuang Song ◽

Jian-Guo Zhang ◽

Gui-Xia Ma ◽

Kai-Bei Yu

Keyword(s):

Thermal Stability ◽

Aqueous Solutions ◽

Diffraction Analysis ◽

Single Crystals ◽

Slow Evaporation ◽

X Ray Diffraction ◽

Element Analysis ◽

Thermal Stabilities ◽

X Ray ◽

Thermal Stability Of

Cobalt(II) and zinc(II) complexes of ethyl carbazate (ECZ), [Co(ECZ)3](NO3)2 and [Zn(ECZ)3] (NO3)2, were synthesized. Single crystals of these two compounds were grown from aqueous solutions using a slow evaporation method. Their structures have been determined by X-ray diffraction analysis. Both of them are monoclinic with space group P21/n. The complexes are further characterized by element analysis and IR measurements. Their thermal stabilities are studied by using TG-DTG, DSC techniques. When heated to 350 °C, only metal oxide was left for both complexes.

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Polystyrene/Montmorillonite Nanocomposites: Study of the Morphology and Effects of Sonication Time on Thermal Stability

Journal of Nanomaterials ◽

10.1155/2013/650725 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 20

Author(s):

Mashael Alshabanat ◽

Amal Al-Arrash ◽

Waffa Mekhamer

Keyword(s):

Electron Microscopy ◽

Thermal Stability ◽

Solution Method ◽

Sonication Time ◽

X Ray Diffraction ◽

Transmission Electron ◽

Polystyrene Matrix ◽

Before And After ◽

Silicate Layers ◽

Thermal Stability Of

Polymer nanocomposites of polystyrene matrix containing 10% wt of organo-montmorillonite (organo-MMT) were prepared using the solution method with sonication times of 0.5, 1, 1.5, and 2 hours. Cetyltrimethylammonium bromide (CTAB) is used to modify the montmorillonite clay after saturating its surface with Na+ions. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the montmorillonite before and after modification by CTAB. The prepared nanocomposites were characterized using the same analysis methods. These results confirm the intercalation of PS in the interlamellar spaces of organo-MMT with a very small quantity of exfoliation of the silicate layers within the PS matrix of all samples at all studied times of sonication. The thermal stability of the nanocomposites was measured using thermogravimetric analysis (TGA). The results show clear improvement, and the effects of sonication time are noted.

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Immobilization of hemoglobin on stable mesoporous multilamellar silica vesicles and their activity and stability

Journal of Materials Research ◽

10.1557/jmr.2005.0360 ◽

2005 ◽

Vol 20 (10) ◽

pp. 2682-2690 ◽

Cited By ~ 15

Author(s):

Yufang Zhu ◽

Weihua Shen ◽

Xiaoping Dong ◽

Jianlin Shi

Keyword(s):

Thermal Stability ◽

Pore Size ◽

X Ray Diffraction ◽

X Ray ◽

Practical Applications ◽

Silica Material ◽

Transmission Electron ◽

Mesoporous Support ◽

Adsorption Desorption ◽

Thermal Stability Of

A stable mesoporous multilamellar silica vesicle (MSV) was developed with a gallery pore size of about 14.0 nm. A simulative enzyme, hemoglobin (Hb), was immobilized on this newly developed MSV and a conventional mesoporous silica material SBA-15. The structures and the immobilization of Hb on the mesoporous supports were characterized with x-ray diffraction, transmission electron microscopy, N2 adsorption-desorption isotherms, Fourier transform infrared, ultraviolet-visible spectroscopy, and so forth. MSV is a promising support for immobilizing Hb due to its large pore size and high Hb immobilization capacity (up to 522 mg/g) compared to SBA-15 (236 mg/g). Less than 5% Hb was leached from Hb/MSV at pH 6.0. The activity study indicated that the immobilized Hb retained most peroxidase activity compared to free Hb. Thermal stability of the immobilized Hb was improved by the proctetive environment of MSV and SBA-15. Such an Hb-mesoporous support with high Hb immobilization capacity, high activity, and enhanced thermal stability will be attractive for practical applications.

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