Siriphannon, Punnama
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Siriphannon, Punnama
Alternative Name
Siriphannon, P.
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punnama.si@kmitl.ac.th
34 results
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Item type:Publication, Preparation of hydroxyapatite/poly(methyl methacrylate) and calcium silicate/poly(methyl methacrylate) interpenetrating hybrid composites(2007-10-01); ; ;Jermsungnern, RapeeRattanabodee, SiriratHydroxyapatite/poly(methyl methacrylate) (HAp/PMMA) and calcium silicate/poly(methyl methacrylate) (CS/PMMA) composites were prepared by interpenetrating bulk polymerization of methyl methacrylate (MMA) monomer in porous structures of HAp and CS. The porous HAp and CS templates were prepared by mixing their calcined powders with poly(vinyl alcohol) (PVA) solution, shaping by uniaxial pressing and then firing at 1,100°C for HAp and 900°C for CS. The templates were soaked in the solution mixture of MMA monomer and 0.1 mol% of benzoyl peroxide (BPO) for 24 h. The pre-composites were then bulk polymerized at 85°C for 24 h under nitrogen atmosphere. The microstructures of the composites showed the interpenetrating of PMMA into the porous HAp and CS structures. Thermogravimetric analysis indicated that the PMMA content in the HAp/PMMA and CS/PMMA composites were 13 and 26 wt%, respectively. Weight average molecular weights (M̄<inf>w</inf>) of PMMA were about 491,000 for HAp/PMMA composites and about 348,000 for CS/PMMA composites. Compressive strengths of these composites were about 90-131 MPa in which they were significantly higher than their starting porous templates. © 2007 Springer Science+Business Media, LLC. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Hydrothermal growth of ZnO nanostructures from nano-ZnO seeded in P(MMA-co-BA) matrix(2011-11-01) ;Pannasri, Piyaphan; ; Nookaew, JitiNano-ZnO synthesized by hydrothermal reaction were embedded in poly(methyl methacrylate-co-butyl acrylate) matrix (P(MMA-co-BA)) to produce the nano-ZnO/P(MMA-co-BA) nanocomposites via in-situ polymerization at 85 °C. The nano-ZnO/P(MMA-co-BA) nanocomposites were hydrothermal treated in the mixture solution of Zn(NO <inf>3</inf>) <inf>2</inf>•6H <inf>2</inf>O and NH <inf>4</inf>OH at 90 °C under various pH (i.e.7, 8, 9 and 10) and treatment time (i.e. 4, 6, 8, 10, 12 and 24 hrs). The nano-ZnO could act as seeding particles for hydrothermal growth of ZnO nanostructures on the surfaces of nanocomposites. The higher pH of basic solutions used in the hydrothermal treatment, the higher amount of Zn(OH) <inf>4</inf> <sup>2-</sup> nuclei would be created, leading to a modification of the ZnO morphology from nano-nuclei to nanorods, nanorods bushes (flower-like nanostructure) and nanofibers with nanospine. The increase of hydrothermal treatment time resulted in the increases of amount and length of multidirectional grown ZnO nanorods. Data of the contact angle measurement exhibited the increase of hydrophobicity of the nano-ZnO/P(MMA-co-BA) nanocomposites after hydrothermal growth of ZnO nanostructures. The nanocomposites treated at pH∈=∈10 for 24 hrs shows the highest hydrophobicity with the contact angle of 121. In addition, the thermal stability of the nano-ZnO/P(MMA-co-BA) could be improved by the formation of hydrothermal grown ZnO nanostructure on the nanocomposite surface. © 2011 Springer Science+Business Media B.V. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Preparation and characterization of hydroxyapatite/poly(ethylene adipate) hybrid composites(2008-06-01); Hydroxyapatite/poly(ethylene adipate) (HAp/PEA) composites were prepared by in situ ring-opening polymerization of cyclic oligo(ethylene adipate) (C-OEA) within the porous HAp templates. HAp was firstly prepared by a co-precipitation method using calcium hydroxide and phosphoric acid and then shaped as a rectangular porous template. PEA precursor was synthesized by bulk polymerization of dimethyl adipate and ethylene glycol in the presence of tetraisopropyl orthotitanate. C-OEA was obtained by cyclo-depolymerization of the PEA precursor under high dilution condition using dibutyl tinoxide as a catalyst. The HAp/PEA composites were prepared by immersing the porous HAp templates in the mixture solution of C-OEA and dibutyl tinoxide catalyst overnight and ring-opening polymerizing at 180, 200 and 220°C for 24 h. The ring-opening polymerized PEA formed as a thin film coating on the surface of porous HAp template. The HAp/PEA composites contained PEA in the range of 20-26 wt%. The weight-average molecular weights of ring-opening polymerized PEA were in the range of 3800-4450 g/mol. Compressive strength of the HAp/PEA composite was significantly increased from 25 MPa in the porous HAp template to 140 MPa in the composite. © 2008 VSP. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Soft solution in situ synthesis of chitosan/iron oxide nanocomposites and their magnetic properties(2021-06-30) ;Vaewbundit, SukandaChitosan/iron oxide nanocomposites (CS/IO) were synthesized by using soft solution in situ synthesis. An aqueous mixture of iron(ii), iron(iii) and chitosan was added drop by drop to a solution of a sodium tripolyphosphate crosslinker with stirring for 30 min, resulting in in situ ionically crosslinked chitosan, with incorporated Fe2+ and Fe3+ (CS/Fe2+Fe3+). The CS/Fe2+Fe3+ precursors were then treated in alkaline solution by two different methods, i.e. hydrothermal and refluxing, where the Fe2+ and Fe3+ ions reacted to form quasi-spherical magnetite-maghemite nanocrystals in the constrained space of the crosslinked chitosan CS/IO nanocomposites. The pressurized hydrothermal system promoted the growth of iron oxide nanocrystals, leading to slightly larger crystallites (3.9-4.3 nm), compared to 3.9 nm from the refluxing system. The iron oxide crystallites also became smaller with increased crosslinking density of the chitosan matrix. The resultant CS/IO nanocomposites exhibited superparamagnetism with Mmax in the range of 9.6-15 emu g-1 and low coercivity and magnetic remanence. In addition, they showed high cell viability, 82-96%, indicating them as potential candidates for medical applications. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Poly(ethylene terephthalate)/hydroxyapatite biomaterials: Preparation, characterization, and in vitro bioactivity(2009-02-01); Poly(ethylene terephthalate)/hydroxyapatite (PET/HAp) composites were prepared by mixing HAp powder with a mixture solution of cyclic oligo(ethylene terephthalate) (C-OET) and dibutyl tinoxide catalyst in dichrolomethane, and then shaping the precomposites in cylindrical pellets. The C-OET in the precomposites was ring-opening polymerized (ROP) to PET under vacuum at 250°C for 24 h. The PET/HAp composites were formulated with HAp to PET ratios of 60:40 (H6P4) and 50:50 (H5P5). The ROP-PET in the composites was present as a thin-layer coating on the HAp grains and evenly distributed throughout the samples. Compressive strength of the PET/HAp composites was significantly increased from 8 MPa of the H10P0 to 17 and 29 MPa for H6P4 and H5P5, respectively. In vitro bioactivity of the PET/HAp composites was studied by soaking in simulated body fluid (SBF) at 36.5°C for 7-28 days. After prolonged soaking, the HAp nanocrystals precipitated from the SBF solution and formed as a layer of globular aggregates, coated on the composite surfaces. The H6P4 composite showed faster formation rate of nano-HAp than the H5P5 composite, indicating that the bioactivity of PET/HAp composites depended on the amount of HAp. © 2008 Wiley Periodicals, Inc. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Nanoencapsulation of n-octadecane phase change material in self-assembled polyelectrolyte by soft solution technique(2014-01-01) ;Iamphaojeen, YuwandaNanoencapsulation of n-octadecane phase change material was performed by facile soft solution technique. An emulsion of n-octadecane and sodium dodecyl sulfate was prepared by high intensity sonication and then mixed with 1-6 mM of poly(diallyldimethylammonium chloride) (PDDA) solution. The capsules with globular core-shell structure were obtained via self-assembly of PDDA molecules coated on the primary emulsion droplets, described as PDDA encapsulated n-octadecane (PDDA-en-Oc). Average particle size and ζ-potential of PDDA-en-Oc increased with increasing of PDDA concentration due to the different PDDA conformation and thickness of capsules' shell. The smaller diameter of PDDA-en-Oc, the faster heat releasing and absorption were obtained. However, the increasing of PDDA concentration could improve the encapsulation efficiency, resulting in an increment of latent heat quantity. The PDDA-en-Oc capsules prepared from 4 mM PDDA with ∼166 nm in size possessed the maximum latent heat and encapsulation efficiency (i.e., 124.4 J/g and 58%, respectively). © 2014 Copyright Taylor & Francis Group, LLC. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Enhanced Photocatalytic and Biological Properties of Cellulose Cotton Fabric Coated with Carboxyethyl Chitosan/Zinc Oxide Bio-nanocomposite(2025-09-01) ;Ayu, Mutiara; This study developed a CECS/ZnO-functionalized cotton fiber sheets as a single-use filter layer for face masks, with enhanced antibacterial and photocatalytic properties. Cotton fiber sheets were modified with zinc oxide nanoparticles (ZnO NPs) using a dip-coating method, with and without carboxyethyl chitosan (CECS) as a binder and stabilizing agent. The fiber sheets were treated with 0.1, 0.3, and 0.5 M Zn(NO<inf>3</inf>)<inf>2</inf> solutions, followed by hydrothermal synthesis in NH<inf>4</inf>OH (Zn:NH<inf>4</inf>OH = 1:2) at 100 °C for 1 h. The study successfully demonstrated ZnO NPs formation on cotton sheets, producing ZnO-immobilized cotton sheets (Cf/Zn). Higher Zn<sup>2</sup>⁺ concentrations promoted greater nucleation of ZnO nanoparticles. However, they also caused particle agglomeration, which reduced the surface area and weakened ZnO adhesion to the cotton fibers. This presents a significant challenge in achieving a uniform nanoparticle distribution. However, the introduction of carboxyethyl chitosan (CECS) (Cf/CECS/Zn) as a binder and stabilizer represents a novel approach that showed a superior ZnO adhesion, better particle distribution, and higher Zn content than untreated Cf/Zn. Among the samples, Cf/CECS/Zn0.1 exhibited the highest Zn content (154 ppm), the highest antibacterial zone diameter (29.39 mm), and the most effective photocatalytic activity (65.66%). While both Cf/Zn and Cf/CECS/Zn demonstrated antibacterial activity against S. aureus, Cf/CECS/Zn0.1 showed superior performance, with low cytotoxicity confirmed by Vero cell viability tests. The treated fibers also displayed enhanced hydrophobic and photocatalytic properties. These results demonstrate the potential of CECS-modified ZnO-immobilized cotton sheets for advanced healthcare filtration applications, offering enhanced antibacterial, photocatalytic, and non-toxic properties. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Mechanical properties and bioactivity of calcium silicate/poly(ethylene terephthalateco-caprolactone) composites(2013-12-01) ;Suebwongnat, S.; Calcium silicate/poly(ethylene terephthalate-co-caprolactone) (CS/PET-co-PCL) composites were prepared via ring opening polymerisation (ROP) technique. The CS/PET-co-PCL composites were prepared by mixing 60 wt-% of CS, 40 wt-% of cyclics and dibutyl tinoxide catalyst (3 mol.-% with respect to cyclics). The cyclics consisted of the mixture of cyclic oligo(ethylene terephthalate) (COET) and e-caprolactone (CPL) with varying molar ratio of C-OET/CPL, i.e. 7 : 3, 8 : 2 and 9 : 1. The precomposites were then ring opening polymerised at 200°C for 24 h. The ROP-PET-co-PCL in the composites was present as a continuous phase impregnated with the CS particles. The 1HNMR spectra of ROP-PET-co-PCL extracted from the CS/PET-co-PCL composites showed heterolinkage signals between PET and PCL at d 4·4 and d 4·6 ppm, indicating successful copolymerisation. When the PCL content increased, the ROP-PET-co-PCL changed in the copolymer structure from block to random structure. The presence of CS powders in the CS/PETco- PCL composites resulted in high stiffness of the composites and inhibited heat dissipation during the dynamic mechanical analysis performed between 250 and 200°C. The compressive strengths of all the composites were in the range of 16-21 MPa. The higher the PET content, the stronger the CS/PET-co-PCL composites obtained. Composites containing 9 : 1 of C-OET/CPL polymerised at 200°C possessed the highest compressive strengths of 21·3 MPa, falling in the range of cartilage bone, i.e. 14-59 MPa. Bioactivities of the CS/PET-co-PCL composites were studied by soaking in simulated body fluid for 7 days. All CS/PET-co-PCL composites could induce the formation of hydroxyapatite nanocrystals on the composite surfaces, indicating the bioactivity of the CS/PET-co-PCL composites. © W. S. Maney & Son Ltd. 2013. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, High Density Polyethylene/Calcium Silicate Hybrid Composite: Preparation, Characterization and In Vitro Bioactivity(2023-01-01); The high density polyethylene/calcium silicate (HDPE/CS) hybrid composites were prepared using a twin-screw extruder and shaped into test specimens using a compression molding machine. The CS loadings, limited to a total of 20 %vol, were incorporated in HDPE matrix. The morphological behavior, thermal behavior, mechanical properties and bioactivity of the composites were investigated and compared with the neat HDPE under identical conditions. It was found that poor dispersion of the CS particles was observed in the composites with high CS loadings because of only weak interaction between CS particles and HDPE. The percentage of HDPE crystallinity was insignificantly changed when adding CS particles in the HDPE/CS composites. The stiffness of the HDPE/CS hybrid composites was strongly improved and reached the maximum values of flexural and compressive moduli at 1190 MPa (35% greater than the neat HDPE) and 581 Ma (17% greater than the neat HDPE), respectively, with 15 % CS loading. The higher the CS loading, the greater the hardness of the HDPE/CS composites were seen. However, the flexural strength of the HDPE/CS composites (up to 15% CS loading) was not considerably altered. Moreover, both flexural and compressive properties were lowered with higher CS content (20%) due to the generated voids in the HDPE/CS composites. After soaking in simulated body fluid (SBF) at 36.5°C for 7–49 days, the HDPE/CS composites could induce the formation of ball-like HA aggregates covering on the composite surface, indicating its bioactivity. This research successfully prepared HDPE/CS hybrid composites with fast rate bioactivity and their modulus and strength values were within those for human trabecular bone. Therefore, the HDPE/CS hybrid composites had potentially used as bioactive materials for medical applications. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, In situ ring-opening polymerization of hydroxyapatite/poly(ethylene adipate)-co-(ethylene terephthalate) biomimetic composites(2013-02-01); Hydroxyapatite/poly(ethylene adipate)-co-poly(ethylene terephthalate) biomaterials (HAp/PEA-co-PET) have been prepared by ring opening polymerization (ROP) of cyclic oligo(ethylene adipate)-co-oligo(ethylene terephthalate) (C-OEA-co-C-OET) in the porous hydroxyapatite (HAp) scaffolds at 250 °C for 24 h under vacuum. The content of ROP-PEA-co-PET in the HAp/PEA-co-PET composite was about 20 wt% with the values of number average molecular weight (Mn) and weight average molecular weight (MW) of 3380 and 7160 g/mol, respectively. Compressive strength and modulus of the HAp/PEA-co-PET composites were about 29 and 246 MPa, respectively. These mechanical properties were higher than those of the porous HAp templates and natural cancellous bone. In vitro bioactivity of the HAp/PEA-co-PET composites was studied by soaking in simulated body fluid (SBF) under the flowing system at the rate of 130 mL/day for 7, 14, 21 and 28 days. The formation of hydroxyapatite nanocrystals was observed on the composite surfaces through the consumption of calcium and phosphorus from the SBF solution, indicating the bioactivity of these HAp/PEA-co-PET composites. These results indicated the competency of HAp/PEA-co-PET composites for biomedical applications. © Indian Academy of Sciences.
