24^th World Congress on Nanomaterials and Nanotechnology July 12-13, 2018 Bangkok, Thailand

Ms. Suttibut is a student at Department of Chemistry, Faculty of Science, Mahidol university,Thailand.

Natural rubber (NR), derived from Hevea brasiliensis, has attracted a lot of attention due to its high molecular-weight (MW) and good mechanical properties. However, there are some limits of usage because it has no reactive terminal group leading to its low compatibility with other functional groups or additive. Recently, chemical modification was interested to modify and improve these lacks, for example, reducing the MW and introducing some functional groups resulting in the functionalized low MW NR (FLNR). The photochemical degradation process, the technique used to prepare the functionalized low MW NR (FLNR), looks more promising method due to the cleanliness, low energy/cost consumptions. In this work, FLNR was prepared in the presence of H2O2 in latex state and using TiO2 film coated on hollow glass bead (TiO2-HGB) as a photocatalyst. The reaction was carried out under 1 kW of ultraviolet-A (UVA, λmax 365 nm) irradiation. The successful coating of TiO2 film on HGB was confirmed by scanning electron microscopy fitted with element analysis accessory (SEM/EDX) and X-ray diffraction technique (XRD). In case of FLNR preparation, deproteinized natural rubber (DPNR) latex was uesd as a starting material. From the structural analysis, the obtained FLNR indicated the presence of hydroxyl, carbonyl and epoxide groups with no crosslinking reaction. The MW of FLNR reduced to around 0.34x105 g/mol. In addition, the TiO2-HGB could be re-used up to 4 times without the damage of film.

Mr. Kongsut is a student at Mahidol university, with a major in chemistry

Natural rubber latex is an exellent elastomeric material which contains a wide rubber particle size distribution including small rubber particles (SRP) and large rubber particles (LRP) . The NR latex is widely used for producing various dipping rubber products. It is well known that mechanical properties of dipped products depend on latex film formation process. Therefore, in the present work, the effect of particle size on the film formation behavier of NR latex was investigated.The SRP and LRP latex was successfully prepared by centifugation of the NR latex at various speeds. Particle size of the obtained SRP and LRP latex was characterized by Light scattering technique, which showed size of the SRP in range of 200 nm. The relationship of particle sizes and film formation was investigated by study the film compaction time. It was found that the film compaction time increased when particle size of NR increased. Moreovre, the effect of particle size on film formation at long time storage was studied. The morphology of samples were characterized by atomic forced microscopy (AFM). The result show that SRP film showed smoother surface than LRP film at the initial stage. Base on the present finding, it can be dedued that different particle size of NR latex is an important parameter, which effect on the film formation behavior.

Ms. Surakhai is a student at Department of Chemistry, Mahidol University.

Macadamia nut shell wastes were transformed to “Macca carbon (MC)” under high carbonization process. The MC revealed high characteristic such as nano-size, high porosity, rich minerals and generation of anions. Significantly, it could generate Far-infrared rays (FIR) with wavelengths in the range of 4-20 µm. Due to its high utilities, it might be applied to develop the efficiency in a non-woven multifilament composite yarn between the MC and polypropylene (PP). To study the effect of FIR from the MC, the sweaters from knitting with and without MC in PP were kept into an oven under halogen lamp at 10 min. It was found that the temperature of the MC composited sweater was enhancer than that of the control about 2˚C. Moreover, the sweater knitted with and without MC were wear in the volunteer and then, they stayed in a room that had 40˚C-controlled at 10 min to control the adjustment of body temperature. The average body temperature of volunteers wearing the sweater without MP was lesser than in the case of volunteers wearing sweater composing of MC, approximately 1.5˚C. Hence, it could be concluded that the preparation of multifilament yarn from the MC-PP composite was successfully in a productive yarn

Shinjini Mitra has completed her B.Sc. in Microbiology in 2011, and her M.Sc. in Microbiology in 2013, from the University of Calcutta, Kolkata, West Bengal, India. She stood 1st in University Examination for Graduation in Microbiology in the Univeristy of Calcutta. She joined the Immunology & Regenerative Medicine Research Laboratory of the Department of Zoology, University of Calcutta, Kolkata, in 2014, and has been working for her Ph.D. since then, on the topic of “Translational Outcome Research in Preclinical Models of Inflammation & Degeneration, using Phytochemicals, Small Molecules and Cell- Based Strategies”.

The main aim of drug discovery is to design drugs which can target specific cells and simultaneously exert its therapeutic effect. The use of polymer- based nanoparticles is useful because their functional components either help direct the drugs to specific cells, or act as drugs themselves from within the cells. In this study, we have used a nanoparticle designed from guar gum, a gum obtained from the seeds of the leguminous plant, Cyamopsis tetragonoloba. It is a galactomannan, with mannose and galactose present in a 2:1 ratio. The guar gum nanoparticle (GN), of size 80 nm, was designed by the acid hydrolysis of the guar gum, and was made mannose- rich. The aim of this study was to determine the therapeutic effect of GN in vitro and in vivo in inflammatory disease. The in vitro studies performed with RAW 264.7 macrophage cells showed successful uptake of GN in a short duration of time, via their mannose receptors, as confirmed by using mannose as a competitive inhibitor. The in vitro anti-inflammatory activity of GN on RAW 264.7 cells was confirmed by nitric oxide (NO) and cell proliferation (MTT) assays. Since the in vitro studies showed an involvement of macrophages, we used GN in a mouse model of thioglycollate- induced peritonitis. Several assays, including flow cytometry, showed a significant decrease in the inflammation with administration of GN. Thus, we concluded that GN can be successfully used as an anti- inflammatory agent for peritonitis.

Ms. Sriwarom is a student at Department of Chemistry, Faculty of Science, Mahidol University,Thailand.

Natural rubber (NR), obtained from Hevea brasiliensis, and synthetic IR consist of cis-1,4-polyisoprene as a major component. For NR, it consisted of many non-rubber components(NRCs) such as proteins, lipids, carbohydrate and inorganic compounds, affecting directly their mechanical properties, whereas IR did not have NRCs. The final product of NR usually exhibited excellent properties, such as high tensile and tear strength and minimal heat buildup, often superior to synthetic polyisoprene (IR). The different properties of NR and IR is related to the formation of network structure from proteins and phospholipids through intermolecular hydrogen bonding in NR. Therefore, the effect of proteins and phospholipids on strain-induced crystallization (SIC) of un-vulcanized NR was investigated in this work. NR was eliminated protein and phospholipid by using deproteinization and tranesterification, respectively. Fourier-Transform Spectroscopy (FTIR) was used to confirmed successful destruction of protein and phospholipid in NR. The behavior of molecular model and SIC of un-vulcanized NR was characterized by using wide-angle X-ray diffraction (WAXD) techniques. Moreover, the SIC behavior in un-vulcanized NR was investigated in tensile strength by perform tensile testing. It was found that crystallizability decreased with the removal of protein and disappeared in transesterificated-DPNR (TE-DPNR). Additionally, both of deproteinized NR (DPNR) and TE-DPNR showed that very low tensile strength. Overall, the naturally occurring network, formed by proteins and phospholipids, is responsible for high stress-strain behavior and crystallization under deformation of un-vulcanized NR.

Kanpitcha Amornjiarasak is a graduate student at polymer science and technology, Mahidol University.

styrene butadiene rubber (SBR) has wide variety of applications such as footwear, conveyor belts and especially tire. However, their usage is limited due to their inert hydrocarbon nature. A method used for improving properties of rubber latex is an introduction of some polar reactive like hydroxyl group onto the molecular main chain. A chemical modification herein was offered to prepare functionalized rubber latex via photocatalytic reaction using TiO2 film as a catalyst. The appropriate TiO2 film was prepared by spin-coating technique, followed by calcination at 550 °C. The efficiency, crystalline form and topology of TiO2 were analyzed by the degradation of methylene blue (MB), XRD and AFM respectively. The photocatalytic activity of TiO2 film decreased in each time of use, nevertheless performance of TiO2 film could be recovered under a long period of UV-cleaning. Subsequently, the functionalization of SBR was investigated under UV irradiation with presentation of TiO2 film. Several techniques were used for characterization of modified SBR: FT-IR, ATR, and 1H-NMR spectroscopy. The hydroxyl functional group of SBR was observed after 3 h of irradiation, using 20% H2O2 and UV 80W.