bluuebunny/crossref_metadata_2025 huggingface dataset:
Research and Design of the Control System for Natural Gas Heater
Authors: Guo Yun , Huang Zhi Qiang , Yang Shun Xin
Published: November 2013

Natural gas heaters are widely used in gas-fired power plants to meet the combustion needs and to improve the combustion efficiency. For the control features and technical requirements of the natural gas heater, the computer automatic control system for natural gas heater has been designed,and realizes the temperature and liquid level real time measurement and control. The system increases significantly the control accuracy of natural gas temperature, eliminates potential unsafety and improves production efficiency.
Efficient Recursive Dynamics and Real Time Simulation of Flexible Space Robots System
Authors: Tian Fu Yang , Li Yu Dao , Wang Zhen , Li Fa De
Published: November 2013

As space robots gain more and more importance in space operations, it was becoming imperative to understand their distinctive dynamics. The dynamics model of the space flexible robots is very complex, and the differential equation derived from dynamics was solved difficultly and slowly. In this paper the efficient recursive O(n) dynamics algorithm of space flexible robots systems with rigid base and flexible manipulators was discussed, and the fast efficient integration method was used to solve this dynamics equation for real time simulation. Simulations results show that the dynamic modeling and fast efficient numerical integration techniques of flexible space robot proposed in this paper are very useful. Keyword: space robots;efficient dynamic; recursive; real time simulation
Optimization and Simulation on Pressure-Reducing Valve in Water Hydraulic Vane Pump
Authors: He Xiao Feng , Deng Ben , Huang Xing , Yan Xue Wen
Published: November 2013

High contact stress between the vane tips and the cam ring is one of the main obstacles to improve the working pressure of a water hydraulic vane pump. A pressure-reducing valve for regulating the bottom pressure of the vanes at the pump suction zone is presented in this paper. Through optimization and simulation, it is found that the throttle structure has great influence on the dynamic performance of the pressure-reducing valve, and the triangular-rectangular groove is proved to be more suitable for the valve among all the investigated grooves. The theoretical analysis results show that the use of the pressure reducing valve can obviously reduce the contact forces between the cam ring and the vanes at the suction zone of the pump. The work in this research provides a feasible solution to improve the working pressure of a water hydraulic vane pump.
Numerical Simulation of Binary Alloy Crystal Growth Using Phase-Field Method
Authors: Dong Yan Bo , Chen Ming , Wang Xi
Published: November 2013

The competitive growth of multiple dendrites and crystal growth of directional solidification in a Mg-Al binary alloy were simulated using phase-field model, and the effect of undercooling value on the microstructural dendritic growth pattern in directional solidification process was studied in the paper. The simulation results showed the impingement of the adjacent grains, which made the dendrite growth inhibited in the competitive growth of multiple dendrites, and in directional solidification process, quantitative comparison of different undercooling values that predicted the columnar dendrite evolution were carried out. With the increasing of the undercooling value, the dendrite tip radius and second dendrite arms became smaller, and the crystal structure is more uniform and dense.
Finite Element Analysis and Structural Optimization of Mine Man-Car Skip Underframe
Authors: Zhang Yie Yie , Kong Ling Qiong , Shi Jie
Published: November 2013

Mine man-car skip underframe is one of key components of mine hoisting system, in order to obtain the optimal structure and function characteristics, the finite element analysis method based on ANSYS is used to make static and modal analysis for the mine slope ramp man-car skip underframe. Static analysis shows that: The strength of underframe under typical working conditions meets requirements, but the stress surplus is relatively large. Modal analysis indicates that: It's prone to have bend and torsional deflection between the 4th and 5th beam, and the free modal shape has saltation. According to the above finite element analysis results, corresponding structure optimization is made on the underframe section size and the position of beams. The optimizing results show that: The stress amplitude of structural optimized underframe increases by 16.9%, the stress surplus effectively reduces, and the weight of underframe decreases by 10.6%. The free modal shape is more smooth, vibration mode has no saltation, and the dynamic performance is improved.
Accurate Mathematical Model of Profile Curve Generated by Pre-Grinding Hob and Three-Dimensional Simulation of the Gear Generation
Authors: Yang Kai Ming , Liu Zhao Zhao , Wang Wei Fang , Guan Li Wen
Published: November 2013

This paper illustrates a method to establish the theoretical equations of profile curve of gear teeth generated by the pre-grinding hob. Matrix computation and differential geometry are employed to derive the equations. Graphics of numerical examples based on the mathematical equations are interpreted using Matlab. The proposed model draws the conclusion about the proper parameters of the teeth profile for the optimization of hob design for industrial application. Furthermore, a three-dimensional model of the pre-grinding hob is built with Pro/E in parametric form as a supplementary approach. It is a descriptive-geometry-based method to generate the gear directly without mathematical derivation. By changing parameters that affect the geometry of a hob tooth profile the hobbing cutter can be constructed to generate any conjugated gear through the motion simulation. With the aid of exact mathematical model and computer program, efficiency of gear machining can be improved by eliminating the traditional trial and error procedure. Keywords-pre-grinding hob; antenna; differential geometry; theoretical equation; parametric design; simulation of generation.
Mechanism Design of the Automatic Adjustment of the Number of Inserting Fuses of the Inserting Fuse Machine for Firecracker
Authors: Liu Guo Ping , Wang Wei Qiang , Cai Zhi Yong , Hu Rong Hua
Published: November 2013

Currently, its problems are about feeding more and inserting less fuses at a time, needing triple cooperation of rotary pairs, locations, and low production efficiency. A new type of feed of fuses mechanism was designed, its automatic adjustment of the number of inserting fuses can come out by means of the transmission fit of the trapezoidal axis with the via holes. The axis is a quadrangular prism in the middle and circular cylinders on both sides and the holes are in the middle of the pulling roll wheel pieces. It greatly improves the production efficiency.
Application of UG/WAVE Technology in the Design of Automobile Front Axle
Authors: Guo Lei
Published: November 2013

In this paper, principles and methods of UG / WAVE technology and the main function of WAVE are introduced, designs of some parts in the automobile front axle illustrates the steps and methods of UG / WAVE top-down modeling. Automatic update feature of the technology can shorten the design cycle, greatly reduce the duplication of design, make the design and management of product is very convenient and efficient, improve the market competitiveness of enterprise, and full play to concurrent engineering advantages.
The Research and Application on Illumination Model Algorithm of Oilfield Virtual Reality System
Authors: Wu Wen Zhen , Sun Kai
Published: November 2013

Realistic graphics for virtual reality system has been a hot research at home and abroad, the illumination model mapping and its application of the algorithms is one of the key level to achieve realistic scenes. This paper introduced the illumination model mapping and classification of the algorithms, focused on ray tracing algorithms and bounding box technology of the global illumination model which were realized in the oilfield virtual reality system and have been achieved good results.
SAR Image Denoising Using an Improved Adaptive Bitateral Filter
Authors: Wang Hua Zhang , Huang Qin Zhen
Published: November 2013

Synthetic aperture radar (SAR) images are inherently affected by multiplicative speckle noise. The presence of speckle damages radiometric resolution, at the same time, it hampers the human interpretation and scene analysis for SAR images. On the base of studying and analyzing the mathematical model of the bilateral filter, the paper proposed a modified adaptive bilateral filter (MABF). First, it separates non-independent two-dimensional Gaussian filter into two independent one-dimensional Gaussian filter, which improves the operation speed greatly. Then through the effective noise parameter estimation, it adaptively selects optimal parameters, which improves the filtering effect. The real SAR image data is used to test the presented method and the experimental results verify that MABF is feasible and effective.
Design and Application of Real-Time Flight Information Acquisition System
Authors: Li Yan , Liu Yan Feng , Shi Zhi Yuan , Yang Feng
Published: November 2013

In the radar target validation systems, the flight information as an important external information source occupies the irreplaceable position. However, in the resent researches, how to obtain the flight information stays focused and unsolved. The Real-time Multi-task Flight Information Acquisition System we designed and realized in this paper could obtain the flight information in real time and provide the real-time, reliable, detailed and complete flight information for the detective area. This system has already successfully used in Airway-nonairway Classification in an ATCRS (Air Traffic Control Radar System).
Emulsion Polymerization of Methyl Methacrylate and Butyl Acrylate Using Non-Ionic Polyurethane as Emulsifier
Authors: Zheng Jie , Xie Guo Hao , Hu Xin , Peng Huan An
Published: November 2013

In this paper, non-ionic polyurethane surfactant which has real good surface activity and better emulsifying capability was totally substitute low molecular weight surfactant for preparing polyacrylate emulsion without any other stabilizer. Kinetics of polymerization was studied and the results showed polymerization with a high rate in initial period and nucleation period was is inversely proportional to the surfactant concentration. The morphology of particles was sphere with core-shell structure. Mechanical testing results shows latex film composed with PUS IGM2000 is better than the one with PUS IGM1000.
A Novel Traffic Flow Forecasting Method Based on the Artificial Neural Networks and Intelligent Transportation Systems Data Mining
Authors: He Wei , Lu Tao , Yu Cheng Qiang
Published: November 2013

Useful information often hides in traffic management system. To mine useful data, prior knowledge has been used to train the artificial neural network (ANN) to identify the traffic conditions in the traffic information forecasting. Subjective information has hence been introduced into the ANN model. To solve this problem, a new ANN model is proposed based on the data mining technology in this work. The Self-Organized Feature Map (SOFM) is firstly employed to cluster the traffic data through an unsupervised learning and provide the labels for these data. Then labeled data were used to train the GA-Chaos optimized RBF neural network. Herein, the GA-Chaos algorithm is used to train the RBF parameters. Experimental tests use practical data sets from the Intelligent Transportation Systems (ITS) to validate the performance of the proposed ANN model. The results show that the proposed method can extract the potential patterns hidden in the traffic data and can accurately predict the future traffic state. The prediction accuracy is beyond 95%.
Application Research of Memory Alloy Washer on Power Equipment Safety and Energy Saving
Authors: Chen Tian Xiang , Fang Xiao Lin , Tian Hong
Published: November 2013

Contact resistance is an essential cause of electrical equipment joint heating. An experimental platform was built to measure and compare temperature and contact resistance of memory alloy spring washers and ordinary spring washers when heated by taking the same heavy current, on condition that both of the counterparts had the same initial contact resistance and temperature. Results showed that memory alloy washer were more helpful to limit the joint temperature rise by reducing contact resistance from their features of tempting to restore to original shape when heated to a high temperature. Therefore, the memory alloy washers were proved to have remarkable effect on ensuring safety of electric power equipments and reducing energy loss.
The Flooding Tolerance and Growth Characteristics of 2 Woody Species by Flooding Durations for Aquatic Ecosystem Restoration
Authors: Koo Bon Hak , Leem Wi Ryong , Park Miok
Published: November 2013

This study was carried out to select the suitable plants for aquatic ecosystem restoration such as lakes and streams. In this study, 2 woody species were investigated for their survival and growth characteristics in the complete and partly flooding condition with 1day, 3days and 5days flooding durations. Flooding tolerance ofRosa multiflorais high and available on half flooded conditions, and no tolerance on complete flooded conditions except 1day flooding. And flooding tolerance ofSpiraea prunifoliais high and available when flooded within 3days. Consequentially, it realized thatRosa multifloraandSpiraea prunifoliaknown as upland terrestrial plants are available in aquatic ecosystems also, and it is realizedRosa multiflorais more effective thanSpiraea prunifolia.
Exploring the Effect of Organizational Dynamic Capability on Data Quality-BI Success Relationship
Authors: Kokin Sergey , Wang Tien An
Published: November 2013

There is growing use of business intelligence (BI) success for better decision-making in many organizations. However, there is a lack of empirical studies on BI Success in academic research. Data Quality is of high importance to employees on every organizational level. The present research investigates Data Quality-BI Success relationship from an organizational dynamic capability perspective. Organizational dynamic capability is the ability to sense and respond to market opportunities and threats with speed, and BI can be of great use in that sensing role of organizational dynamic capability. Drawing on the dynamic capabilities framework, and literature about business intelligence and data quality, we hypothesize that BI Success and Data Quality relationship is moderated by organizational dynamic capability. A research model was developed to define the relationship of BI and Data Quality with organizational dynamic capability. Survey data were collected and used to assess the model. The results of the research show that better data quality is of significant value for organizations, as well as it can be a source of organizational dynamic capability and competitive advantage.
Effect of Sintering Aids on the Densification of Andalusite Ceramics
Authors: Wu Jian Feng , Cheng Hao , Xu Xiao Hong , Deng Teng Fei
Published: November 2013

The ceramics with large bulk density and high bending strength were fabricated via semi-dry pressing and pressureless sintering in the air. Andalusite and calcined bauxite were used as the raw materials, sintering aids such as potassium feldspar, albite, talc, spodumene and borax were added to promote the densification and decrease the sintering temperature of the samples. The best physical properties were obtained on a sample of optimal composition (the addition of sintering aid was talc) sintered at 1500 °C for 3 h, i.e. a bending strength of 138.52 MPa and bulk density of 2.61gcm-3, the sintering temperature was lower than sample without addition of sintering aid.
Power Transfer Coefficients between Two 3D Semi-Infinite Solids in EFEA Formulation
Authors: Chen Xi Liang , Zhang Wen Wu
Published: November 2013

The energy finite element analysis (EFEA) is more effective for analyzing high frequency vibration problem compared to the traditional finite element method (FEM). When applying the EFEA to complicated structures, it is necessary to obtain power transfer coefficients at structural joints. This paper proposes the theoretical formulations of computing power transfer coefficients between two 3D semi-infinite solids, and demonstrates the validation of the developed theoretical formulations through two examples with different incident waves: dilatational wave and distortional wave.
Modeling, Analysing and Simulation – Way to Good Operation Phase of Residential Stock
Authors: Česelský Jan , Berankova Eva Wernerova
Published: November 2013

The period of the crisis characterized by the stagnation of economy sectors has an impact especially on building activities where a large part of them is housing construction. In the field of housing, this situation has an adverse effect not only on the level of further quantitative development, but especially in the form of the suspension of the basic reproduction of housing resources that is necessary for maintaining the state of housing. The housing property management and maintenance process currently undergo greater pressure caused by budgets of the portfolio owners. The challenge of this time is to turn partially away from looking for ways of advancing and financing new housing construction and to focus primarily on optimizing the management and maintenance of the existing house and flat resources in order to maximize capacity utilization, on looking for saving, new possibilities, technologies, and tools with emphasis on the flexibility and complexity of services, and on finding ways how to set about these services as efficiently as possible for the benefit of the owners and tenants under the condition of substantial cost reductions. One of these possible tools, which is not too much known yet and is still underused in the Czech environment but which has the great potential for benefits to optimizing and improving the effectiveness of management and maintenance in the future, is BIM (Building Information Modeling).
Magnesium Ferrite Powder and its Composite Electrospinning Nano-Fiber Preparation
Authors: Guo Min , Zhang Tong Hua , Dong Jing , Cheng Lan
Published: November 2013

This paper investigates a magnetic fiber made of magnesium ferrite particle and PVA. Magnesium ferrite particles were prepared using chemical co-precipitation method and characterized by FTIR spectra, size distribution and magnetism. In addition, the morphology of magnetic fibers was studied by SEM. Results show that magnesium ferrite particles present pretty good magnetism and quite uniform size distribution. With an increasing content of magnesium ferrite particle, the volume and mass of magnetic microspheres increase on the fiber surface.
Encapsulation of Vitamin E in Glassy Carbohydrates by Extrusion
Authors: Chang Da Wei , Zhang Xiao Ming , Kim Jin Moon
Published: November 2013

Vitamin E (VE) was encapsulated in glassy carbohydrates by extrusion. Four typical formulations were prepared in order to have 5% and 8% VE added to each 20% and 30% modified starch containing feed material, all four formulations contained soya lecithin at 1% level as an emulsifier. The physico-chemical properties of glassy extruded products were investigated. The results showed that the VE retention rates were above 93%, meanwhile the VE oil was dispersed uniformly throughout the carbohydrate mass after extrusion. There was a slight loss for VE during the storage. The glass transition temperature (Tg) of the extrudates were above 30°C and Tg could be a good predictor of caking properties at elevated temperatures.
Effect of Mixing Temperature on the Mechanical Dynamic and Morphological Properties of Maleated Natural Rubber/Copolyester Blends
Authors: Lamlaeh Suwaiyah , Kaesaman Azizon , Nakason Charoen
Published: November 2013

Maleated natural rubber/copolyester (MNR/COPE) blends with different mixing temperatures were prepared by using an internal mixer (Brabender® GmbH & Co.KG, Duisburg, Germany). The effect of mixing temperatures on mechanical, dynamic and morphological properties has been investigated. It was found that the mixing temperature at 190 ̊°C provided the blend with the highest tensile strength. While the mixing temperature at 170 °C showed superior elastomeric properties, in terms of tension set and tan δ with the finest morphology.
Investigation of Structure-Properties Relationship of High Performance TPV Based on ENR/TPU
Authors: Kalkornsurapranee Ekwipoo , Nakason Charoen , Pichaiyut Skulrat , Kummerlöwe Claudia , Vennemann Norbert
Published: November 2013

Thermoplastic natural rubber based on blending of ENR-50/TPU and un-modified NR/TPU was prepared via dynamic vulcanization technique. Influences types of natural rubber (i.e., un-modified NR and ENR-50) on mechanical and morphological properties of the blends were investigated. It was found that the blends with ENR-50 exhibited superior properties than that of the blend with unmodified NR. This is attributed to the interactions between the functional groups of ENR molecules and polar functional groups in TPU molecules which caused higher interfacial adhesion and interaction between both phases. The chemical interactions were confirmed by ATR-FTIR. Furthermore, it was found that the ENR-50/TPU blend showed smaller and finer grain morphology compared with the un-modified NR/TPU.
Assessment of Mixing Efficiency of Intermeshing Rotor Mixers on Morphological and Mechanical Properties and Crosslink Density of Dynamically Vulcanized EPDM/PP Blends
Authors: Uthaipan Nattapon , Junhasavasdikul Banja , Nakason Charoen , Thitithammawong Anoma
Published: November 2013

The mixing efficiency of intermeshing rotor internal batch mixers for the preparation of rubber-rich thermoplastic vulcanizates (TPV) based on ethylene propylene diene terpolymer (EPDM) and polypropylene (PP) blends was investigated. Two laboratory scale mixers, namely intensive batch mixer (INS) and kneader batch mixer (KND), were used. The mixer choice at controlled mixing conditions was investigated to determine its effects on morphological and mechanical properties and crosslink density of the prepared EPDM/PP TPVs. Such effects were found on the degradation of the polymer, on the distribution of the EPDM phase in the blend morphology, particularly the size of EPDM inclusion, and on the crosslink density of the EPDM phase. In summary, the different mixing efficiencies of INS and KND type mixers affect the EPDM/PP TPVs and their properties. Also, the INS mixer has higher mixing efficiency than the KND mixer.
Comparative Study of NR/BR/PP and NR/NBR/PP Ternary Blends for High Abrasion Resistant Thermoplastic Vulcanizates
Authors: Inted Soriya , Lopattananon Natinee , Thongnuanchan Bencha , Kaesaman Azizon
Published: November 2013

High abrasion thermoplastic vulcanizates (TPVs) based on natural rubber (NR)/butadiene rubber (BR)/polypropylene (PP) and NR/acrylonitrile butadiene rubber (NBR)/PP were prepared using melt blending method. The rubber blends of 40/60 NR/BR and 40/60 NR/NBR were firstly prepared to investigate their mechanical and wear-resistant properties. The results indicated that the abrasion resistance of NR/BR blend was much higher than that of the NR/NBR blend, but the tensile strength and elongation at break were lower. TPVs made of NR/BR/PP and NR/NBR/PP blends were then prepared by melt-mixing the rubber blends (i.e., NR/BR or NR/NBR) and PP with composition of rubber to plastic of 60/40. It was found that the NR/BR/PP TPV showed higher strength and abrasion resistance when compared with the NR/NBR/PP TPV due to smaller domain of vulcanized rubber particles. The present study also suggested that the abrasion resistance of NR/BR/PP TPV was slightly lower than that of nylon 6.
Effect of Fillers from Renewable Resources on the Performance of Novel Heat and Oil Resistant Thermoplastic Vulcanizates Based on Epoxidized Natural Rubber/Thermoplastic Polyurethane Blends
Authors: Pongdong Wiphawadee , Nakason Charoen , Kummerlöwe Claudia , Vennemann Norbert
Published: November 2013

Thermoplastic vulcanizates (TPVs) based on thermoplastic polyurethane (TPU) and epoxidized natural rubber (ENR) were prepared by dynamic vulcanization. In this study, the influence of different types and loading levels of filler on the properties of ENR-25/TPU blends was investigated. Furthermore, a filler from renewable resources, namely Rice Husk Ash (RHA), and conventional silica were incorporated in the blends (i.e., premixed with ENR-25). Then, various loading levels of filler were investigated at 10, 20 and 30 phr and compared with the unfilled blend. It was found that the incorporation of filler into the blend shows higher complex viscosity, mechanical properties in terms of Youngs modulus, tensile strength and hardness compared with the TPV without filler. The incorporation of ENR-25 into the blend shows lower hardness than pure TPU. It was also found that TPV filled with RHA revealed almost identical values for Youngs modulus, tensile strength, elongation at break and hardness, than the same TPV filled with conventional silica. This indicates rice husk ash has great potential to be used as filler in polymer composites based on ENR/TPU blends.
Pore Formation of Natural Rubber Film Comprising Different Liquids
Authors: Phaechamud Thawatchai , Issarayungyuen Pongsathorn , Pichayakorn Wiwat
Published: November 2013

Typical natural rubber (NR) foam could be produced by an addition of some blowing agents in dry NR. The porous topography of this produced material is interesting for applying in field of pharmaceutical science and related. For this study, the porous natural rubber structure was attempted to be fabricated by casting technique. The addition of various grades of polyethylene glycol into NR solution was performed before casting however there was no apparent pore formation. Olive oil and distilled water could not induce the pore formation whereas propylene glycol, triethyl citrate and NMP addition exhibited the ability to induce the pore formation in NR matrix film. This obtained structure will be tested and used as controlled drug delivery.
On the Performance of Hybrid Natural Rubber Rubberized Concrete
Authors: Suchat Sunisa , Aditapsatit Paisin
Published: November 2013

Waste rubber is an environmental concern. The large global market of concrete products could usefully consume this waste, even if the fractions used were very low, provided such concrete mix had sufficient strength and other characteristics. Therefore, the properties of concrete mixes that include natural rubber were studied at 28 days of age, which is a standard time to characterize hardened concrete properties. We included two types of natural rubber in this study, namely natural rubber latex (NRL) and discarded rubber glove. First, 60% concentrate latex (HA: high ammonia) was used in latex per cement ratio 0.10 by volume. Second, discarded rubber gloves, passed through a #6 sieve with 3.36 mm size, were used to investigate effects of soft rubber particles, on strength and insulation properties of lightweight concrete. The hybrid rubberized concrete mixes had 0%, 10%, 20% and 40% partial substitution of sand by volume, at water-cement ratio of 0.45 by volume. Density, compressive strength, flexural strength, insulation property, and coefficient of thermal conductivity were measured. A small 10% fraction of rubber particles improved flexural strength. However, compressive strength decreased with the amount of rubber in concrete. The thermal conductivity was slightly lower than that of normal concrete. Natural rubber addition can produce a moderately lightweight concrete, with good thermal insulation, and the inclusion of rubber glove waste in concrete aggregate appears feasible. Applications could also include non-primary structural uses with medium to low strength requirements, benefiting from other features of concrete. The results suggest that waste rubber can be used to create value-added concrete composites with sufficient structural strength, and improved thermal insulation.
Cure Characteristics and Spectroscopic Studies of Silica Filled Epoxidised Natural Rubber Compound
Authors: Kamal Mazlina Mustapha , Bakar Rohani Abu
Published: November 2013

Reinforcement of rubber by precipitated silica is adversely affected due to lack of strong polymer filler bonding1-2. The surface energy of fillers play an important role in the reinforcement of rubbers and has a profound influence on the performance of rubber products3. Functionalised polymers interact strongly with surface silanol groups of precipitated silica. In this work, the unique reinforcement mechanism exhibited by silica in Epoxidised Natural Rubber (ENR) is established through rheometric and Fourier Transform Infrared Spectroscopic (FTIR) study. A rheometer torque rise was detected with an ENR compound silica in the absence of any curing agent. On the other hand, the extent of the interaction increased with the increment of epoxidation level. Fourier transform infra red spectroscopic studies showed silica is bonded to ENR through formation of Si-O-C bond and the extent of the chemical interaction depends on the moulding time4.
Utilization of Recovered Palm Oil Fuel Ash as a Filler for Epoxidized Natural Rubber Composite: Influence of Filler Loading on Curing, Mechanical and Morphological Properties
Authors: Intharapat Punyanich , Nilcharn Rattanawadi , Kongnoo Aroon
Published: November 2013

Palm oil fuel ash (POFA) is used as a filler in epoxidized natural rubber containing 50 mole percent of epoxide groups (ENR-50). The potentiality of ENR-50 composite filled with POFA is investigated through the effect of different POFA loadings in a range of 0-60 phr on cure characteristics, mechanical properties and morphology. The chemical compositions and structure of POFA are also studied. It shows that POFA contains the major compositions of silicon dioxide or silica at 43.0 %wt and calcium carbonate at 20.3 %wt. The IR spectrum represents the important functional group of silanol. The cure characteristics of the composites are improved by reducing scorch time and optimum cure time with increasing POFA loading from 20-50 phr. However, they tend to increase slightly at high loading of POFA (i.e., 60 phr). Torque values (i.e., mimum torque, maximum torque and torque difference) increase with increasing POFA loading up to 40 phr, and then it decreases. Tensile strength of rubber vulcanizates containing POFA loading level at 40 phr exhibits the highest value. For elongation at break, it decreases while hardness increases regarding the increase of POFA loading. Morphology of the composites reveals that POFA particles show uniform dispersion and distribution in rubber matrix, but it moves toward the agglomerates formation at POFA loading beyond 40 phr.
Influence of Surface Modification and Content of Nanosilica on Dynamic Mechanical Properties of Epoxidized Natural Rubber Nanocomposites
Authors: Jarnthong Methakarn , Nakason Charoen , Peng Zheng , Lopattananon Natinee
Published: November 2013

Epoxidized natural rubber (ENR) nanocomposites were prepared in latex state by using unmodified and modified surface of nanosilica. Influence of surface modification and content of nanosilica on dynamic mechanical properties as a function of frequency (i.e., complex viscosity (η*), storage modulus (G ́) and loss modulus (G”) of ENR nanocomposites were investigated. It was found that surface modification of nanosilica improved rheological properties of nanosilica filled ENR nanocomposites. Moreover, greater nanosilica contents caused increasing of η*, G ́ and G”.
Tensile Properties, Swelling Behavior, and Morphology Analysis of Recycled High Density Polyethylene / Natural Rubber / Chicken Feather Fibers (R-HDPE / NR / CFF) Composites: The Effects of Caprolactam
Authors: Supri A.G. , Izzuddeen Mohammed
Published: November 2013

The effect of caprolactam as a coupling agent on the tensile properties, swelling behavior and morphology analysis of recycled high density polyethylene/ natural rubber/ chicken feather fiber (R-HDPE/ NR/ CFF) composites was studied. The R-HDPE/NR/CFF composites with and without caprolactam were prepared using Brabender Plasticorder at 160°C and rotor speed of 50 rpm. The results indicated that R-HDPE/NR/CFF with caprolactam showed higher value of tensile strength but lower elongation at break and mass swell percentage than R-HDPE/NR/CFF composites. SEM morphology showed that the addition of caprolactam improved the fiber matrix-interfacial adhesion and good dispersion of the fiber in the R-HDPE/NR blends.
Characteristics of NR/CB Composites: Preparation Methods and Correlations of Electrical and Mechanical Properties
Authors: Thongruang Wiriya , Nooklay Benjaporn , Bunnaul Pitsanu , Spontak Richard J. , Smithmaitrie Pruittikorn , Chetpattananondh Kanadit
Published: November 2013

This work aims to correlate the electrical conductivity and mechanical properties of binary composites made of natural rubber (NR) and carbon black (CB). The samples were prepared using both a wet and dry mixing method before making the composites with a conventional rubber vulcanization process. The dry-mixing method was found to achieve higher electrical conductivity than the wet-mixing method. The composite made by efficient vulcanization (EV) had lower compression set than the composite made by conventional vulcanization (CV) and the compression set increased with an increase of CB. The highest tensile strength of the composite was found at CB content of 20 phr. The percolation threshold concentration of the binary composite was observed at 10 phr CB. Electrical conductivity of the composite depended on sample thickness where thinner samples had higher conductivity than the thick sample.
Carbon Nanotube Elastomer Composites
Authors: Kummerlöwe Claudia , Vennemann Norbert , Siebert Achim
Published: November 2013

Composites of multi walled carbon nanotubes and several synthetic rubbers as well as natural rubber were investigated regarding their mechanical properties, electrical and thermal conductivity and vulcanization properties. The composites were prepared by a melt mixing process. Induction and cure times obtained from rheometer curves exhibited a considerable decrease with increasing filler loading and kinetic investigations using a first order model indicated a distinct reduction of the activation energy. An examination of the crosslink density by equilibrium swelling and hysteresis tensile testing showed a strong increase with carbon nanotube content. The analysis of the thermal conductivity revealed the presents of a considerable interfacial thermal resistance which restricts the contribution of carbon nanotubes to the composite thermal conductivity. The electrical percolation thresholds of the melt compounded composites depend on processing procedure as well as elastomer and CNT type. At least a partial exfoliation of the CNT aggregates was reached.
 Preparation of New Polyols Based on Cis-1,4-Polyisoprene by Using 1,3-Dipolar Cycloaddition
Authors: Anancharoenwong Ekasit , Pilard Jean Francois , Campistron Irène , Laguerre Albert , Gohier Frédéric , Bistac Sophie
Published: November 2013

This research focuses on synthesis and modification of polyol precursors derived from cis-1,4-polyisoprene (PI). These new polyol precursors can be converted to high value-added polyurethane (PU). The epoxidized hydroxytelechelic PI (EHTPI) prepared by chemical modification from PI was used as starting material for polyol synthesis. 1,3-Dipolar cycloaddition between a terminal alkyne and an azide has rapidly become the most popular click reaction. We applied this reaction to couple azide-functionalized PI and alkyne-functionalized sugar for preparing polyols. For azide functionalization, 1-methyl epoxidized cyclohexane was used as a model molecule, and various conditions for epoxide ring opening of 1-methyl epoxidized cyclohexane and EHTPI were investigated. The cycloaddition of alkyne and azide was carried out in the presence of sodium ascorbate and copper sulfate. The polyol precursors obtained might be used to prepare biodegradable polyol PU.
An Optimization Study on the Inclusion of Aluminium Hydroxide into Natural Rubber Latex as Deproteinization Agent
Authors: Keuw Wei Lim Keuw , Badri Khairiah Haji , Ban Wong Chong
Published: November 2013

A preliminary study was conducted to investigate the effect of aluminum hydroxide (ATH) as a deproteinizing agent in commercial natural rubber latex (NRL) onto the physicochemical properties of the NRL. The loading of ATH in NRL was varied at 0.05 parts per hundred rubbers (phr), 0.10 phr, 0.15 phr and 0.20 phr. The optimum amount of ATH in NRL was determined from pH value, mechanical strength time (MST), protein content and Fourier Transform Infrared spectroscopy. The addition of ATH in NRL reduced the protein content of NRL (3.52%) to the lowest (1.19%) at 0.15 phr ATH. Protein-aluminate complex was detected from the FTIR spectra through peak at 3498 cm-1, referred to as C-N-H functional group.
Value Adding of Skim Natural Rubber by Grafting with Maleic Anhydride
Authors: Somboonchai Sudarat , Opaprakasit Pakorn , Pattamaprom Cattaleeya
Published: November 2013

This research investigates the potential for grafting skim natural rubber with maleic anhydride to produce maleated rubber with the aim to increase value of skim natural rubber. In this study, grafting of skim natural rubber was compared to those of natural rubber block. Moreover, the effect of protein in skim rubber was also investigated by comparing with grafting of deprotinized skim rubber. Here, the grafting reactions were carried out by reactive melt-mixing method. The effect of maleic anhydride concentration and type of raw materials were investigated. Quantities of the grafted anhydride (MA) and the amount of double bonds were determined by using FTIR analysis.We found that nitrogen content of raw material could potentially affected the grafting level, especially at low MA content, and that the grafting reaction occurred in parallel with crosslinking reaction(gel). The potential model of reaction mechanism was analyzed from FTIR spectra and the gel content.
Effect of Ground Tyre Rubber Devulcanisates on the Properties of a Passenger Car Tyre Tread Formulation
Authors: Dayang A.I.H. Habibah , Saiwari Sitisaiyidah , Dierkes Wilma , Noordermeer Jacques W.M.
Published: November 2013

Extensive research on recycling processes, in particular for waste tyre material, is necessary due to increasing raw material costs, diminishing resources and growing awareness of environmental issues. One of the preferred methods is devulcanisation, in which only sulphur cross-links are broken, while the polymer chains remain intact. In this study, optimised processing conditions for the devulcanisation of whole passenger car tyres using diphenyldisulphide (DPDS) as a devulcanisation aid were applied. The devulcanised ground tyre rubber (D-GTR) obtained from the process was blended on top of the original tyre tread formulation at different concentrations. The cure characteristics and mechanical properties of the re-vulcanised blends are evaluated in comparison to the original compound. The results so far indicate that the addition of D-GTR influences the properties of the blend, but to a lesser extent than the commercially used powder or reclaim types do, for which loadings less than 5% can be applied. The main reason for the influence of D-GTR on the rubber properties is inhomogeneities in the D-GTR/virgin rubber blend.
An Application of Lean Supply Chain Management for Cost Reduction in Latex Industry
Authors: Ponpakdee Suwanna , Sirivongpaisal Nikorn , Suthummanon Sakesun , Kongkaew Wanatchapong , Penchamrat Pallapat
Published: November 2013

The objective of this research is to reduce the total systemwide cost of the latex industry supply chain, including three significant stakeholders, who are rubber plantation (farmer), latex factory, and glove factory. The lean concept is employed to investigate the wastes and to propose alternative methods for eliminating them. The value stream mapping technique (VSM) is used as a tool to identify non-value added activities in the supply chain. There are three main steps for this research, 1) create a supply chain model for latex industry, 2) assess the current state of the supply chain by evaluating value added (VA), non-value added (NVA) activities and the total supply chain cost, 3) move toward the future state by analyzing root causes and identifying countermeasures to eliminate wastes. The result indicates that the largest percentage of the total systemwide cost is the storage cost of raw materials and finished goods, which is accounted for 58.35%. The further research will be created forecasting technique and design collecting point field latex for reduce labor cost in supply chain.
Keywords Lean Supply Chain Management, Latex Industry, Cost Reduction
Natural Rubber Latex Foam Loading with Metronidazole
Authors: Issarayungyuen Pongsathorn , Nithi-Uthai Nattapong , Pichayakorn Wiwat , Phaechamud Thawatchai
Published: November 2013

Normally, natural rubber latex foam (NRLF) has been produced from natural rubber latex with centrifugation and addition of foaming agent such as ammonium olaete. In this study, the different porosities of NRLFs were loaded with metronidazole (MET), the antibiotic and powerful antiprotozoal agent. NRLFs topography, water uptake and erosion properties were studied. Release of MET from NRLFs was performed in phosphate buffer pH 7.4 at 37°C and the cumulative amount of MET liberation was determined by UV-Vis spectrophotometer. NRLFs exhibited the apparent porous structure with highly water uptake and no erosion. Burst release of MET from NRLFs was noticed for all NRLFs. Therefore, the MET-loaded NRLFs were properly suitable for fast release and their dramatically porous topography was applicable for high loading capacity of selected active compounds.
Thermal and Mechanical Properties of Mulch Film from Poly(Lactic Acid)/Expoxidized Natural Rubber Blends Filled with Rutile TiO2 as Fillers
Authors: Nuinu Pranee , Samosorn Kittikorn , Srilatong Kittisak , Tongbut Siripa , Saengsuwan Sayant
Published: November 2013

The aim of this research was to reduce and improve the brittleness and thermal properties of poly lactic acid (PLA), respectively. Epoxidized natural rubber (ENR) was used to enhance the toughness and rutile titanium dioxide (R-TiO2) as filler was also incorporated to improve the thermal properties of the PLA. 10wt% ENR with epoxidation contents of 25 mol% (ENR25) and 50 mol% (ENR50) and various R-TiO2contents (0-10 phr)were compounded with PLA by using a twin-screw extruder at 155-165°C and a rotor speed of 40 rpm. The pellets of blends were then formed a thin film using a cast film extruder machine and cooled down under air flow. Thermal and mechanical properties and morphology of PLA/ENR/R-TiO2thin film were investigated. The crystallinity of PLA was found to increase with addition of ENR. The mechanical properties of thin film showed that the ENR50 enhanced the elongation but reduced the tensile strength of PLA with addition of R-TiO2at 5 and 10 phr, respectively. The TGA indicated that the addition of 10 phr R-TiO2increased in the decomposition temperature at 5% weight loss (Td5%) of PLA/ENR film. Thus the thermal stability of PLA/ENR50 was found to improve with addition of R-TiO2. From morphology study, the ENR50 phase showed a good dispersion in the PLA matrix. In conclusion, the addition of ENR and R-TiO2was found to enhance both toughness and thermal stability of PLA.
Influence of Curing Systems on Mechanical, Dynamic, and Morphological Properties of Dynamically Cured Epoxidized Natural Rubber/ Copolyamide Blends
Authors: Romin Rawviyanee , Nakason Charoen , Thitithammawong Anoma
Published: November 2013

Thermoplastic elastomers (TPEs) based on dynamically cured epoxidized natural rubber/copolyamide (ENR/COPA) blends were prepared. Influence of curing systems (i.e., sulphur, peroxide, mixed sulphur and peroxide and phenolic resin cured systems on mechanical, dynamic and morphological properties of the blends were investigated. It was found that the blend with phenolic cured system exhibited superior mechanical and set properties. That is higher tendency to recover to its original shape after a prolong extension. It was also found that the blend with peroxide cured system exhibited higher storage modulus and complex viscosity than those of the blends with mixed sulphur and peroxide, phenolic and sulphur cured system, respectively. Furthermore, the TPVs blend with peroxide cured system showed the smallest vulcanized rubber particles.
Thermoplastic Natural Rubber of Co-Polyamide: Effect of Blend Ratios on Mechanical, Swelling, Dynamic and Morphological Properties
Authors: Sripornsawat Boripat , Kaesaman Azizon , Nakason Charoen
Published: November 2013

Maleated natural rubber (MNR) was synthesized and formulated to prepare thermoplastic natural rubber (TPNR) by blending with co-polyamide (COPA). It was found that 100% modulus, tensile strength, elongation at break, hardness and degree of swelling increased with increasing proportion of COPA. However, degree of swelling and tension set value decreased which reflects enhancing of rubber elasticity. Dynamic properties were also determined by a rotor less oscillating shear rheometer (Rheo Tech MDpt). It was found that increasing proportion of MNR caused increasing of storage modulus and complex viscosity but decreasing tan δ value. Morphological properties were also determined by SEM technique. It was found that the MNR/COPA simple blends with the proportion of rubber 40, 50 and 60 wt% exhibited the co-continuous phase structures.
rhBMP-2 Induces Immature Muscular Tissue to Differentiate into Bone-Like Tissue In Vitro
Authors: Hayashi Tatsuhide , Yoshihara Kentaro , Kawase Mayu , Mieki Akimichi , Kataoka Hiroyasu , Hamajima Soichiro , Kawai Tatsushi
Published: November 2013

The aim of this study is to induce bone from immature muscular tissue in vitro using recombinant human BMP (rhBMP)-2 and expanded polytetrafluoroethylene (ePTFE) as a scaffold. Commercially available rhBMP-2 was used in this experiment. IMTs were harvested from the forelimbs of 20th Sprague-Dawley embryonic rats and placed into a homogenizer with 10ng/μl of rhBMP-2 and then homogenized. The homogenized IMT was placed on ePTFE and cultured for 2 weeks. The analyses of histological observation, electron probe micro analyzer (EPMA), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were carried out following culture. The bone-like tissue, which was made up of osteoblast-like cells and osteoids, was partially observed by H-E staining. Moreover, strong mineral deposition was observed in the extracellular matrix by von Kossa staining. Ca, P and O were detected in the extracellular matrix by EPMA and were confirmed to be at almost the same position based on the findings of synchronized images. XRD patterns and FTIR spectra of specimen were found to have typical hydroxyapatite crystal peaks and spectra, respectively. These results suggest that rhBMP-2 induced IMT differentiation into bone-like tissue in vitro.
Preparation and Characterization of Micro-Nanostructured Anatase Film
Authors: He Meng , Cheng Kui , Weng Wen Jian
Published: November 2013

Micro-nano structured TiO2 films were prepared by hydrothermally seed layer-induced synthesis. The results showed that the films were composed of TiO2 platelets in size of 2μm~10μm. The maximum distance between platelets was ~4 μm. There were TiO2 nanodots (seed layer) in size of ~100nm between TiO2 platelets. This structured film was proven to be anatase and more anatase was detected along with hydrothermal synthesis. Water contact angle varied from 103° to 149° along with hydrothermal synthesis and all films showed super-hydrophilicity after UV illumination. These micro-nano structured films obtained in this study could potentially applied in many biomedical applications, e.g., osseointegration film and cell sheet technology, owing to its excellent biocompatibility and UV switchable super-hydrophilicity.