bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Property Testing of Compatibilized Poly(l‐lactide)/Thermoplastic Polyurethane Blends
Authors: Suthapakti Kanyarat , Molloy Robert , Punyodom Winita , Nalampang Kanarat , Leejarkpai Thanawadee , Topham Paul D. , Tighe Brian J. 
Published: August 2015

SummaryPoly(l‐lactide) (PLL) has been blended with a polycaprolactone‐based thermoplastic polyurethane (TPU) elastomer as a toughening agent and a poly(l‐lactide‐co‐caprolactone) (PLLCL) copolymer as a compatibilizer. Both 2‐component (PLL/TPU) and 3‐component (PLL/TPU/PLLCL) blends were prepared by melt mixing, characterized, hot‐pressed into thin sheets and their tensile properties tested. The results showed that, although the TPU could toughen the PLL, the blends were largely immiscible leading to phase separation. However, addition of the PLLCL copolymer improved blend compatibility. The best all‐round properties were found for the 3‐component blend of composition PLL/TPU/PLLCL = 90/10/10 parts by weight.
The Potential of Perlite as an Odour‐Adsorbing Fillers in Natural Rubber Vulcanizates
Authors: Rattanaplome Tithinun , Pornprasit Philaiwan , Chantaramee Napat 
Published: August 2015

SummaryThe objective of this research was to reduce an offensive odour by using perlite as an odour‐adsorbing filler. Perlite was mixed with highly odorous STR20 and RSS5. Perlite content was varied at 0, 10, 20 and 30 phr. The ability to reduce odour by sensory method and GC‐MS were examined. Cure characteristics and mechanical properties, such as tensile strength, hardness and abrasion resistance, were also determined. From the sensory method, the odour reduction efficiency increased with increasing perlite content.With an addition of perlite, the reduction of some components from an offensive odour, such as thiourea and benzothiazole, was also observed using GC‐MS technique. Furthermore, the addition of perlite showed an increase in torque difference, a slight change in scorch time and a decrease in cure time, an increase in hardness and abrasion resistance but a decrease in tensile strength. Perlite was shown to be comparable to clay with respect to mechanical properties and potentially be used as low‐cost and odour‐adsorbing filler.
Crystallization of Double Crystalline Diblock Copolymer by Dynamic Monte Carlo Simulation
Authors: Kundu Chitrita , Dasmahapatra Ashok Kumar 
Published: August 2015

SummaryWe report dynamic Monte Carlo simulation results on the crystallization of double crystalline A‐B diblock copolymer, wherein the melting temperature of A‐block is higher than B‐block. Crystallization of A‐block precedes the crystallization of B‐block upon cooling from a homogeneous melt. The interaction between A‐type and B‐type units is modelled as the repulsive interaction to represent their mutual immiscibility. The morphological development is controlled by the interplay between crystallization and microphase separation. With increasing segregation strength, we observe a gradual decrease in crystallinity accompanying with smaller and thinner crystals. During crystallization, A‐block crystallizes first and creates confinement for the crystallization of the B‐block. Thus, crystallization of B‐block slows down, influencing the overall crystal morphology. With changing block composition, we observe a non‐monotonic trend in the crystallization behaviour (viz., crystallinity, lamellar thickness) of A‐block when B‐block composition is significantly higher than A‐block. This non‐monotonic trend is attributed to the dilution effect of the B‐block.
Effect of Vegetable Oils as Processing Aids in SBR Compounds
Authors: Pechurai Worawan , Chiangta Warunee , Tharuen Pariya 
Published: August 2015

SummaryThis research was studied on the cure characteristics and mechanical properties of rubber compounds using vegetable oil as the processing aid in styrene butadiene rubber compound such as castor oil and jatropha oil in comparison with petroleum based aromatic oil. The quantities of the oils varied from 0 to 9 phr. The study showed that the cure characteristics in terms of maximum torque and torque difference tended to decrease with increasing concentrations of oils, while scorch time and cure rate index increased. Moreover, hardness and 100% modulus tended to decrease as increasing loading levels of the oils in the SBR vulcanizates while elongation at break increased. However, tensile strength was not significantly affected. For using the vegetable oils, we found that abrasion resistance and rebound resilience were better than those of aromatic oil, and also displayed high hardness. It could be concluded that the vegetable oils were better alternative processing aids compared to aromatic oil, which has been reported as carcinogenic.
Biopolymer‐Nanocomposites with Silica, Alumino‐Silicate and Graphene: Structural Characterization and Properties
Authors: Mittal Vikas , Patwary F. , Chaudhry Ali U. , Luckachan Gisha E. 
Published: August 2015

SummaryMechanical, rheological and thermal properties of melt processes bio‐nanocomposites of poly(butylene succinate) (PBS) and chitosan blends with 0‐dimensional and 2‐dimensional nanofillers were studied. The weight ratio of PBS and chitosan in the blend was optimized based on ease of processing, mixing quality and mechanical performance. The chitosan phase was observed to be dispersed as non‐continuous phase in PBS and enhanced it mechanical properties markedly. The fillers had different degrees of improvement in the mechanical performance with graphene exhibiting a maximum increase of > 225% in the Young's modulus at 10% filler content. The IR characterization also signaled toward chemical interactions between the polymer and graphene phases. Increasing the filler content had overall reduction in crystallinity.
Potential Antibacterial Activity of Polystyrene Nanoparticles/Chitosan Coated on Cotton Fabrics
Authors: Siralertmukul Krisana , Watcharamul Supawin , Wicheanpaisan Natthakrita , Nuisin Roongkan 
Published: August 2015

SummaryThis research is to study the potential of using polystyrene nanoparticles and chitosan solution to increase the anti‐bacterial activity on cotton fabrics prepared by a conventional pad‐dry‐cure method. Firstly, cotton fabrics were coated with chitosan solutions at the concentrations of 0.1, 0.5, and 1.0 (%w/v) and tested for the antibacterial property which was determined by clear zone measurement and viable count assay using Escherichia coli (ATCC 25922) as a tested microorganism. The results showed that, the percentage bacterial reductions were 87.2, 86.3, and 48.5%, respectively, when the cotton fabrics was coated only with chitosan solution. When polystyrene nanoparticle solution was coated onto cotton fabrics prior to coating with chitosan solutions at the concentrations of 0.1, 0.5, and 1.0 (%w/v), the percentage bacterial reductions were 90.3, 90.8, and 65.5%, respectively. This indicated that coating the cotton fabrics with polystyrene nanoparticles prior to chitosan coating would remarkably increase the antibacterial activity. The scanning electron micrographs showed that polystyrene nanoparticles were aggregated and inserted in between the interfiber spacings. The thin film of chitosan was also observed on the surface of cotton fabrics and hydrophobic property of the fabrics was tested via contact angle measurement.
Biopolymer Films Based on Chitosan and Polyethylene Glycol with Pineapple Leaf Fiber for Food Packaging Applications
Authors: Ninjiaranai Padarat 
Published: August 2015

SummaryPineapple is a tropical plant native to South East Asia. Pineapple leaf fiber is rich in cellulose, relatively inexpensive and abundantly available. Furthermore, it has the potential for polymer reinforcement, and is more environmentally friendly than films that are reinforced with the artificial additives. The objectives of the present work were to compare the mechanical and water vapor barrier properties of biopolymer films, chitosan and polyethylene glycol 6000 (PEG 6000), with and without incorporating pineapple leaf fibers which had been chemically treated in an alkaline solution. The water vapor permeability (WVP), % soluble matter (SM), moisture index, tensile strength (TS) and % elongation (E) were investigated in these films. The composite yellow film exhibited an excellent water vapor permeability of 5.14 ± 1.87 g mm m−2day−1kPa−1. The solubility was 65.00 ± 0.97% while the moisture index was in the range of 10.50‐31.20%. The results suggested that biodegradable films could be advantageously used to replace polymer films in the packaging of freshly processed vegetables and thereby reduce the negative environmental impact of polymeric films.
A New Crosslinker for the Preparation of Silk Fibroin Hydrogels
Authors: Suttenun Nuchada , Punyamoonwongsa Patchara 
Published: August 2015

SummarySilk fibroin (SF) hydrogels has recently been explored as promising matrices for biomedical applications due to their excellent biodegradability, biocompatibility and hydrophilicity. Despite these, native SF hydrogels showed poor water resistance with typical uncontrollable gelation kinetics. To overcome these drawbacks, a new method of chemical crosslinking using O'O‐bis[2‐(N‐succinimidyl succinylamino) ethyl]polyethylene glycol (NHSP) as a homobifunctional protein crosslinker was employed. A crosslinking reaction, performed under physiological conditions, was completed within 24 hours, producing a hybrid interconnected porous architecture. This network formation contributed to the shortened gelation kinetics and was confirmed by the appearance of a new IR absorption peak of the ether linkage (1102–1104 cm−1). A new thermal degradation temperature found at 430 °C also reconfirmed the presence of such newly‐formed covalent network within the samples. In addition, NHSP could induce a silk phase transformation from the α‐helices into the β‐sheets, as convinced by the shifts of the amide absorption bands (Amide I, Amide II and Amide III), illustrating their strong intermolecular interactions. The new proposed method has thus, proven its potential use to render the silk‐based materials for controlled drug delivery applications.
Properties of Dual Cured Polyurethane Film Coatings Based on Natural Rubber
Authors: Thitithammawong Anoma , Rungvichaniwat Adisai , Srangkum Suthasinee 
Published: August 2015

SummaryDual curable polyurethane (PU) material coating was prepared from natural rubber based polyol. The end capping technique was applied to terminate the PU prepolymer chains with thiol and acrylate monomers. The end capped PU coatings had improved physical and mechanical properties as well as curing time. The developed end capped PU prepolymers or PUDUALs obviously reduced paint defects. A 2/1 molar ratio of thiol/acrylate monomers prominently gave a PUDUAL coating with properties comparable to a commercial PU coating.
Study on Reuse of Diphenyl Disulfide‐Devulcanized Natural Rubber from Truck Tires
Authors: Saiwari Sitisaiyidah , Waesateh Kamaruddin , Lopattananon Natinee , Thititammawong Anoma , Kaesaman Azizon 
Published: August 2015

SummaryThe post‐consumer rubber in truck tires can be converted to a valuable raw material by de‐vulcanization. Natural rubber (NR) from used truck tires (UR) has been recycled by thermo‐chemical de‐vulcanization using DPDS as a de‐vulcanization aid. The de‐vulcanization efficiency is analyzed in term of the soluble fraction and the crosslink density of de‐vulcanizates (D‐UR). The D‐UR has significantly higher soluble fraction and lower crosslink density compared to those of original UR, indicating destruction of the rubber network by the de‐vulcanization. Blends of the D‐UR with virgin NR were also prepared at various blend ratios. D‐UR loading can be up to 40% with acceptable mechanical properties. The curing system and the compounding recipes for the blends were studied to achieve material properties having closely comparable to those achieved with virgin raw materials.
Enhancement of Mechanical Properties of Photo‐Responsive Polymers
Authors: Christogianni Paraskevi , Moniruzzaman Mohammed , Kister Guillaume 
Published: August 2015

SummaryPhotomechanical polymers are characterised by changes in their mechanical properties under light radiation. This process is driven by the reversible isomerisation of chromophores in a polymer matrix. Azobenzene‐based materials can switch their isomeric structure from trans to cis by light of appropriate wavelength. When this class of materials is chemically connected to polymers as a side chain or backbone, the polymers show photo‐induced mechanical property improvements. This paper reports on the photomechanical property changes in a series of copolymers of methyl methacrylate (MMA) and methacryloyloxy azobenzene (MOAB) with azobenzene in the side chains. The chromophore loading ranges between 10% and 65%mol. Nanoindentation was employed to quantify the relationship between the variation in the photo‐driven mechanical properties and the amount of chromophore loading in the copolymer films. Results demonstrated that the stiffness of the polymer films increases up to 19% with an optimum loading of 30%mol azobezene. Above this level of azobenzene loading (30%mol) the stiffness decreases suggesting a maximum effect can be obtained with 30%mol loading in this copolymer matrix. The rate of isomerisation in thin films was established by monitoring the visible spectra before and after irradiation. The duration of trans to cis isomerisation increases with azobenzene loading. The cis to trans isomerisation under visible light is faster than the trans to cis conversion, due to the greater thermodynamic stability of the trans form.
DFT Study of Proton Transfer in Methyl Urocanate and Butyl Urocanate
Authors: Yana Janchai , Chirachanchai Suwabun , Jarumaneeroj Chatchai , Lee Vannajan Sanghiran , Kodchakorn Kanchanok , Tashiro Kohji , Nimmanpipug Piyarat 
Published: August 2015

SummaryDevelopment of proton conductivity is necessary to improve polymer electrolyte efficiency of proton exchange membrane fuel cell (PEMFC) which is alternative environmentally friendly resource. Modification of polymer electrolyte has been employed using water free polymer instead of hydrated polymer membrane to disregard water loss problem at high temperature. Heterocycles such as imidazole and benzimidazole derivatives was considered for anhydrous membrane modification to encourage proton transfer in polymer electrolyte membrane. Alkyl urocanate was interested as a vehicle for proton transfer between side chains of polymer membrane. In this work, investigation of blending of butyl urocanate in polymer membrane to assist the proton transfer ability was carried out. Energy barrier of proton movement between alkyl urocanate was calculated. The preferred orientation of bimolecular alkyl urocanaetes was initiated by crystallographic data. The energies of various proton position in between neighbouring molecules were calculated to determine the barrier of proton transfer. The density function theory (DFT) with generalized gradient approximation (GGA) and BLYP function was used for calculation. The energy barrier of butyl urocanate was found lower than methyl urocanate corresponding to the previous experimental proton conductivity data.
Cellulose Graft Poly(acrylic acid) and Polyacrylamide: Grafting Efficiency and Heavy Metal Adsorption Performance
Authors: Wichaita Waraporn , Samart Chanatip , Yoosuk Boonyawan , Kongparakul Suwadee 
Published: August 2015

SummaryCorn cob cellulose was prepared by alkali‐treatment method and grafted with acrylic acid and acrylamide using ammonium persulphate as an initiator and N,N'‐methylenebisacrylamide as a cross‐linker. The influences of monomer to cellulose ratio, initiator content, cross‐linker content and reaction temperature on grafting efficiency were studied. The maximum grafting efficiency was achieved at 89% at the appropriate condition. Properties of grafted cellulose were characterized by SEM, FTIR, CHNO analysis and TGA. Poly(acrylic acid) and polyacrylamide modified cellulose were used as adsorbents for Cu(II) and Ni(II) removal from aqueous solution. The adsorption capacity was in the range of 8–12 mg g−1 with the removal performance up to 52–99%.
Reusable Modified Natural Rubber Foam for Petroleum‐Based Liquid Removal
Authors: Ratcha Arissara , Samart Chanatip , Yoosuk Boonyawan , Kongparakul Suwadee 
Published: August 2015

SummaryA new kind of natural rubber‐based oil sorbent material was prepared by sulfur vulcanization system. Natural rubber (NR) foam was modified with poly(butyl methacrylate) (PBMA) and poly(butyl acrylate) (PBA) which were prepared by emulsion polymerization. The functionality of pure polyacrylate and modified NR foam were characterized by Fourier transform infrared (FTIR) spectroscopy. Morphology of the modified NR foam was observed by scanning electron microscope (SEM). The oil/water sorption capacity and reusability of modified NR foam were investigated. Sorption test of modified NR foam showed that the modified NR foam were efficiently removed petroleum‐based liquid (viscosities of 0.49–37 cSt) such as gasohol, diesel, engine oil, xylene and toluene. The oil sorption capacity of modified NR foam was in the range of 5–16 g g−1 and maintained oil sorption capacity over the range of 3–15 g g−1 after 20 cycles of absorption. About 95% of foam can be recovered by squeezing or evaporating the oil or organic solvent within the modified NR foam. The results showed that the modified NR foams are promised as reusable oil sorbent.
High Temperature Thermal Gradient Interaction Chromatography (HT‐TGIC) for Blends of Ethylene/1‐Octene Copolymers: A Mathematical Model
Authors: Inwong Nantiya , Anantawaraskul Siripon , Soares João B. P. , Al‐Khazaal Abdulaal Z. 
Published: August 2015

SummaryHigh temperature thermal gradient interaction chromatography (HT‐TGIC) was recently developed to characterize chemical composition distribution (CCD) of ethylene/1‐olefin copolymers based on the interaction between polymer chains and graphitic surface. In this work, a mathematical model of HT‐TGIC was developed based on the population balance in a non‐equilibrium, multi‐stage adsorption/desorption process. Results from the proposed model were found to be in a good agreement with the experimental results of blends over various operating conditions.
Preparation of Green High Impact Polystyrene Beads via Suspension Polymerization
Authors: Kittiwattanakul Tatiya , Prasassarakich Pattarapan , Hinchiranan Napida 
Published: August 2015

SummaryThe aim of this research was to investigate the important effects and their interaction on production of Green High Impact Polystyrene (HIPS) synthesized by using natural rubber (NR) as elastomeric phase via suspension polymerization initiated and stabilized by using benzoyl peroxide (BPO) and poly(vinyl alcohol) (PVA), respectively. The effects of reaction parameters: wt ratio of NR/styrene and PVA/NR including agitation rate on HIPS bead size were studied by using 2k factorial design experiment. The HIPS bead size increased with increasing the NR content (0.01–0.08 w/w of NR/ST) in the mixture of NR/styrene syrup. Whereas, the increase in the PVA content (1.5–2.5 w/w of PVA/NR) and agitation rate (350–450 rpm) decreased HIPS bead size. Thermal gravimetric analysis (TGA) results were showed that HIPS containing the various amounts of NR had more thermal stability than the neat PS. Moreover, the glass transition temperature (Tg) of PS phase in the obtained HIPS bead was shifted from 97.9 to 84.2 °C when the wt ratio of NR/ST was increased to 0.08.
Studies of Different Properties of Polystyrene‐Asphaltene Composites
Authors: Siddiqui Mohammad Nahid 
Published: August 2015

SummaryThe study of thermal and viscoelastic properties of polystyrene composites with different filler loadings of asphaltenes were carried out. The thermogravimetric analysis revealed that the T10 for neat polystyrene was around 365°C and it increased to 440°C with an addition of asphaltene (3 wt% loading, St3). Further addition of asphaltene also showed an increase in the T10 value compared to the neat polystyrene. The second important parameter from TGA analysis can be seen that the neat polystyrene had a degradation maximum (T50) at around 432°C and St3 composite shows the highest T50 value of 450°C. Differential Scanning calorimetric studies of the composites shows that Tg of polystyrene was around 66°C and St2 composite showed the Tg at the maximum of 69°C, which infers that there was interaction between the filler and the matrix. St3 composite shows higher storage modulus as compared to all others. Addition of asphaltenes improved the storage modulus of polystyrene system due to the compatibility effect, which facilitated better load transfer due to the strengthening of the interphase between the filler and matrix. Loss modulus curves of the polystyrene and composites showed a higher loss modulus than the neat polymer in the whole temperature region. It was concluded that the thermal stability and viscoelastic properties of the polystyrene composites were significantly improved with the addition of asphaltene as filler.
Effect of a combined oral contraceptive on patency of arterial anastomosis in a female rat model
Authors: Dadaci Mehmet , Oztekin Can , Oztekin Pelin Seher , Sargon Mustafa Fevzi , Ozgur Figen 
Published: August 2015

BackgroundOral contraceptives, which may lead to thrombotic events, are widely used drugs by women in reproductive age, some of whom might need emergent or elective microsurgical intervention. This study was planned to investigate the effects of combined oral contraceptives (COC) on arterial anastomosis patency in female rat model.MethodsA third generation COC (ethinyl estradiol and desogestrel) was used in this study. A total of 50 female Wistar albino rats were included. The rats were divided into two groups. Experimental group received 0.03 mg ethinyl estradiol/0.15 mg desogestrel with gastric catheter for 20 days before the surgery. Afterward, the femoral arteries of all rats were divided and anastomosed. The patency of the anastomoses were assessed surgically (at 15 min, 7th day) and radiologically with Doppler ultrasonography (at 3rd and 7th days). The samples were examined using light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM).ResultsThe early patency assessed in the 15th min showed arterial flow in all rats. But at the 7th day 68% of the anastomosis were patent in the COC group while 100% of the anastomosis were patent in the control group as demonstrated surgically and radiologically (P = 0.004). Microscopic examination showed an increase in cytoplasmic organelles and activation of endothelial cells in all rats in the experimental group that received COCs.ConclusionThe present study demonstrated the negative effects of the use of COCs on anastomosis patency in rats. © 2015 Wiley Periodicals, Inc. Microsurgery 35:553–559, 2015.