Mechanochemical Assisted Modification of Parawood Microcrystalline Cellulose Using Silane Coupling Agent and their Composites Properties

Surface treated parawood microcrystalline cellulose (PW-MCC) performed under mechanochemical reaction using planetary ball milling at ambient temperature was used as a reinforcing material in polypropylene composites. Initially, PW-MCC was prepared by acid hydrolysis of parawood sawdust pulp. After that, PW-MCC was treated with vinyltrimethoxysilane at milling speed 400 rpm for 60 min. The surface composition from XPS indicated the existence of silicon atom on silane-treated PW-MCC. The thermal stability of PW-MCC was also improved and SEM micrograph revealed rough surface after modification reaction. The untreated PW-MCC and treated PW-MCC were applied to prepare polypropylene composites at 5-30 wt% loading content without a compatibilizer. The results demonstrated that silane-treated PW-MCC/PP composites enhanced tensile strength, thermal stability and water resistance of the composites.

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Utilization of Microcrystalline Cellulose Prepared from Cotton Waste as Reinforcement in Polypropylene Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.488-489.696 ◽

2012 ◽

Vol 488-489 ◽

pp. 696-700 ◽

Cited By ~ 1

Author(s):

Saowaroj Chuayjuljit ◽

Korkaew Palasuth

Keyword(s):

Thermal Stability ◽

Microcrystalline Cellulose ◽

Testing Machine ◽

Dependent Manner ◽

Polypropylene Composites ◽

Thermogravimetric Analyzer ◽

Reinforcing Agent ◽

Cotton Waste ◽

Dose Dependent ◽

Thermal Stability Of

To obtain polypropylene/microcrystalline cellulose (PP/MCC) composites, PP was melt mixed with three loadings (5, 10 and 15 phr) of MCC prepared by hydrolyzing cotton waste with hydrochloric acid. The prepared MCC was characterized for its crystal structure, particle size, thermal stability and morphology. The tensile properties and thermal stability of PP/MCC composites with and without maleic anhydride-grafted polypropylene (MAPP) compatibilizer were investigated using the universal testing machine and thermogravimetric analyzer, respectively. The obtained results showed that the tensile strength, Young’s modulus and thermal stability of the composites were enhanced in a dose dependent manner, whilst the elongation at break was deteriorated with increasing MCC loadings, as compared with the neat PP. However, these properties were all improved with the addition of MAPP into the composites. This work showed that MCC and MAPP could be effectively used as reinforcing agent and compatibilizer, respectively in the PP matrix.

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Effects of Microcrystalline Cellulose on the Thermal Properties of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.1778 ◽

2011 ◽

Vol 284-286 ◽

pp. 1778-1781 ◽

Cited By ~ 5

Author(s):

Zhe Zhou ◽

Hou Yong Yu ◽

Mei Fang Zhu ◽

Zong Yi Qin

Keyword(s):

Thermal Stability ◽

Thermal Properties ◽

Microcrystalline Cellulose ◽

Crystallization Temperature ◽

Solvent Casting ◽

Melt Crystallization ◽

Casting Method ◽

Nucleation Agent ◽

Tga And Dsc ◽

Thermal Stability Of

The composites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with different microcrystalline cellulose (MCC) contents were prepared by a solvent casting method. The effects of MCC on the thermal properties of PHBV were studied by TGA and DSC. The DSC results showed that the melt crystallization temperature of the PHBV/MCC increased from 41.9 °C for PHBV to 59.8 °C for the composites containing 20 wt. % MCC, which indicated that the crystallization of PHBV became easier with the addition of MCC. It also illustrated that the MCC could be used as an effective nucleation agent for the crystallization of PHBV. Moreover, it was found that the thermal stability of the PHBV/MCC composites increased compared with the neat PHBV.

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Study on Acrylic Emulsion Adhesive Modified by Double Siloxane

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.395-396.367 ◽

2013 ◽

Vol 395-396 ◽

pp. 367-370

Author(s):

Cai Hua Gao ◽

Wen Lu Guo ◽

Zhi Ming Jin

Keyword(s):

Thermal Stability ◽

Comparative Study ◽

Heat Resistance ◽

Chemical Process ◽

Water Resistance ◽

Orthogonal Experiment ◽

Acrylic Emulsion ◽

Macroscopic Properties ◽

The Stability ◽

Thermal Stability Of

The acrylic emulsion adhesive was modified by D4 and KH570 with chemical process, and we can get the modified product successfully via the best technology parameter which was confirmed by orthogonal experiment. The structure of acrylic was characterized by FTIR, while there was a comparative study on the macroscopic properties and thermal stability of the unmodified and modified product. The results showed that when m(D4):m(KH570) was 2:1, the dosage of emulsifier was 3.0%, the dosage of KPS was 4.0%, the monomer(soft and hard) ratio was 1:1, the stability of the acrylic emulsion adhesive modified by double siloxane was good, and its viscosity, water resistance, heat resistance were improved greatly.

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Molecular Characterization of Cycloinulooligosaccharide Fructanotransferase from Bacillus macerans

Applied and Environmental Microbiology ◽

10.1128/aem.67.2.995-1000.2001 ◽

2001 ◽

Vol 67 (2) ◽

pp. 995-1000 ◽

Cited By ~ 8

Author(s):

Hwa-Young Kim ◽

Yong-Jin Choi

Keyword(s):

Escherichia Coli ◽

Thermal Stability ◽

Striking Difference ◽

Bacillus Macerans ◽

Specific Manner ◽

Specificity Constant ◽

Processing Event ◽

Hydrolysis Of ◽

Thermal Stability Of

ABSTRACT Cycloinulooligosaccharide fructanotransferase (CFTase) converts inulin into cyclooligosaccharides of β-(2→1)-linkedd-fructofuranose by catalyzing an intramolecular transfructosylation reaction. The CFTase gene was cloned and characterized from Bacillus macerans CFC1. The CFTase gene encoded a polypeptide of 1,333 amino acids with a calculatedM r of 149,563. Western blot and zymography analyses revealed that the CFTase with a molecular mass of 150 kDa (CFT150) was processed (between Ser389 and Phe390 residue) to form a 107-kDa protein (CFT107) in the B. macerans CFC1 cells. The processed CFT107 was similar in its mass to the previously purified CFTase from B. macerans CFC1. The CFT107 enzyme was produced by B. macerans CFC1 but was not detected from the recombinant Escherichia coli cells, indicating that the processing event occurred in a host-specific manner. The two CFTases (CFT150 and CFT107) exhibited the same enzymatic properties, such as influences of pH and temperature on the enzyme activity, the intermolecular transfructosylation ability, and the ability of hydrolysis of cycloinulooligosaccharides produced by the cyclization reaction. However, the thermal stability of CFT107 was slightly higher than that of CFT150. The most striking difference between the two enzymes was observed in their Km values; the value for CFT150 (1.56 mM) was threefold lower than that for CFT107 (4.76 mM). Thus, the specificity constant (k cat/Km ) of CFT150 was about fourfold higher than that of CFT107. These results indicated that the N-terminal 358-residue region of CFT150 played a role in increasing the enzyme's binding affinity to the inulin substrate.

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Preparation and Properties of Silane-Terminated Poly(urethane-Imide)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.1577 ◽

2013 ◽

Vol 690-693 ◽

pp. 1577-1580

Author(s):

Xiao Xi Hu ◽

Yun Wang

Keyword(s):

Thermal Stability ◽

Water Resistance ◽

Tensile Tests ◽

Mechanical Analysis ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Silane Coupling ◽

Ft Ir ◽

And Storage ◽

Thermal Stability Of

A serious of silane-terminated poly (urethane-imide) (Si-PUI) was synthesized via prepolymer method using polycarbonatediols (PCDL), 2,4-tolylene diisocyanate (TDI), 4,4'-Oxydiphthalic Anhydride (ODPA) and silane coupling agent KH-550. The structure of the products was characterized by FT-IR. The thermal properties were measured by thermal gravimetric analysis (TGA). The thermal mechanical behavior was investigated by dynamic mechanical analysis (DMA).The mechanical characteristic was measured by tensile tests. The water absorption (Wa) was also been tested. With the imide content increasing, the thermal stability, tensile strength and storage modulus of poly (urethane-imide) improve significantly, and the glass transition temperature rises. The introduction of silanes improves the water resistance and further enhances the thermal stability of poly (urethane-imide).

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The properties of sericin/poly(vinyl alcohol) films modified by boric acid

e-Polymers ◽

10.1515/epoly.2010.10.1.1567 ◽

2010 ◽

Vol 10 (1) ◽

Author(s):

Qun Wang ◽

Lu Qi

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Boric Acid ◽

Vinyl Alcohol ◽

Water Resistance ◽

Poly Vinyl Alcohol ◽

Scanning Calorimetry ◽

Blend Ratio ◽

Percutaneous Drug Delivery ◽

Thermal Stability Of

AbstractA group of films mainly composed of sericin and poly(vinyl alcohol) (PVA), using boric acid (BA) as a modifier, were prepared by a technique of solution casting. In this work, the effect of BA and sericin on the mechanical properties and water resistance of the films was analyzed, the interior morphology of the films were described by a scanning electron microscopy (SEM), the thermal stability of the films was characterized by differential scanning calorimetry (DSC), and the reaction mechanism was proposed according to the previous literature and the test of Fourier transform infrared spectrum (FTIR). Results indicated that, the properties of the membrane were the functions of the blend ratio of sercin to PVA and the content of BA. The use of BA increased the tensile strength, improved the water resistance and the thermal stability, and varied the interior morphology of the films. The content of sericin greatly influenced the combination of properties of the films, especially the mechanical properties, interior morphology, thermal stability, and water resistance reducing with the increasing of sericin content. The films have potential to be used in materials, such as skin-care coatings for beauty, percutaneous drug delivery systems for exterior intact skin, due to the characteristics of the components and the good mechanical properties of the films.

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