Insulated Sandwich Panels from Natural Rubber and Rubber Wood

ABSTRACTThe focus of this research was to study the properties of insulated sandwich panels created from natural rubber as a core and rubber wood strands as surface layers in order to introduce more sustained components for construction materials. This panel was fabricated under the hot compression at the temperature of 150 ºC to trickle a blowing agent mixed in rubber compounds to decompose and yield amounts of gas leading to a porous rubbery core. This brought the density of this product to reach 410-550 kg/m3 which was about four times lighter than that of the brick and concrete walls. This density was even lower than that of the commercial light weight panels for three times while the strength of the panel from this research was about two times greater. It was also found that the panel from this research revealed the value of thermal conductivity at 0.07-0.08 w/mK which was drastically lower than that of the brick and concrete walls for sixteen times as well as lower than that of the commercial light weight panels for almost two times. Moreover, this panel displayed the value of sound transmission lost at 35-80 dB which was about two times better than that of the wall materials used currently

Consumption pattern and consumers' opinion toward street food in Nakhon Si Thammarat province, Thailand

Street food in NST province is crucial for the people due to the changing of lifestyles. The consumers demand enhances the number of street vendors in the province. Nevertheless, there are vendors that are not practicing good hygienic compared to other province. The objectives of this study are to identify the pattern of street food consumption, and consumers' opinion towards the street food. Observation and in-depth interview were used to collect data. Ten respondents with various demographic backgrounds were interviewed on their experiences, and opinions toward street food. The data found that the street food consuming pattern was formed in six major themes: consumer characteristic, type of food, location, time of consuming, ways to consume and reasons of consuming. Additionally, the study also declared consumer's opinion on the problems related to street food. The finding aims local authority to have more understanding on the culture of street food consumption, and the problems that have been existed to find the appropriate improvement, and do not induce any conflict between local authority with street vendors and authority with consumers

Reliability and validity of consumers’ decision making investigation of safe street food purchasing, pilot study in Nakhon Si Thammarat, Thailand

Although street food has been the sources of unsafe food for consumption in the world including Thailand, it is interesting that many people are still choosing the food from here. The aim of this study is to investigate consumers’ decision making regarding purchasing safe street food. There is very limited research in this area, therefore this study purposes to develop and test the quality of the instrument. The instrument was developed base on purchasing decision making model, and then tested the validity and reliability of data that collected from 150 pilot respondents by using SEM analysis. The results showed the drawn model was fit with the data. Moreover, the construct reliability (CR > 0.7), convergent validity (AVE > 0.5) and discriminant validity (AVE > r 2 ) were acceptable. As a result, this instrument is capable to be applied in main study and test the research hypotheses. This pilot study can confirm that the instrument is workable and minimize the potential problem that probably occurs according to unclear instrument

A smart surface from natural rubber: the mechanism of entropic control at the surface monitored by contact angle measurement

Surface oxidation of crosslinked natural rubber provided a hydrophilic substrate (sticky surface) that became more hydrophobic (less sticky) when equilibrated against hot water. This unusual temperaturedependent surface reconstruction is interpreted as the result of recoiling of entropic unfavorable uncoiled chains induced when rubber surface was oxidized. Subsequent equilibration of these annealed samples against water at room temperature returned their original hydrophilicity. The degree of this surface reconstruction and its kinetics are also dependent on the amounts of crosslinking of the samples

From Natural Rubber to Smart Surfaces

Surface oxidation of crosslinked natural rubber provided a hydrophilic substrate that reconstructed under nitrogen atmosphere at room temperature to become more hydrophobic. Subsequent equilibration against water at room temperature returned its original hydrophilicity. This behavior may arise from the minimization of interfacial free energy of the system by the migration of hydrophilic functional groups away from or to the interface. The change in surface moieties, influences tackiness at the rubber surface - it is tackier when functional groups are at the interface rather than when they migrate away. The magnitudes and kinetics of this surface reconstruction depends on the molecular weight between crosslinks (Mc) and temperature. The results reported here provide information for further development of smart surfaces from crosslinked natural rubber

Factors affecting consumers’ decision making process in Purchasing safe street food in Nakhon Si Thammarat Province, Thailand

Nakhon Si Thammarat (NST) province is one of the cities in Thailand that offers various types of street foods. However, the number of street vendors that the food was certified safe is very low, and there are many consumers who still purchase street food because of their lifestyle. As a result, the consumers may get effect from food risk. Therefore, this research aims to evaluate the significant factors that influence consumers’ decision-making process on safe street food purchasing. The objectives of this research are to identify the individual factor that influences their decision making process, to examine the effects of each variables on each level of consumers’ decision making process, and to evaluate the effectiveness of food safety certification on consumers’ purchasing. Quantitative method was used to examine the influence of various factors on decision making process based on the decision making model of Engel-Miniard-Blackwel (EMB) as well as the Utility Function Theory. Structural Equation Model (SEM) results showed all factors affected the variables in consumers’ decision-making process; the consumers’ motivation (MOTI) affected every stage of the process, the consumers’ food safety knowledge (KNOW) affected the consumers’ need recognition in purchasing safe street food (NEED) and the consumers’ pre-purchase evaluation (PREP) and the consumers’ convenience foodpurchasing lifestyle (LIFE) affected only consumers’ safe food purchasing (PURC). In addition, the variable of the decision making in one stage also affected each variable in the next stage, such as, NEED→PREP, and PREP→PURC. Furthermore, the consumers’ attitude towards food safety certification (CERT) could not moderate PREP→PURC. This study can be utilized by the authorities in order to understand the significant factors when developing strategies that may encourage consumers to purchase safe street food, including effective procedures to promote the food safety certificate. Future study can examine what other factors that might influence consumers’ safe street food purchasing

พฤติกรรมการขับขี่รถจักรยานยนต์กับการมีส่วนร่วมในการป้องกันและแก้ไขปัญหาอุบัติเหตุที่เกิดจากการขับขี่รถจักรยานยนต์: กรณีศึกษาชุมชนตำบล ท่ามิหรำ อำเภอเมือง จังหวัดพัทลุง

การศึกษาครั้งนี้เป็นการศึกษาวิจัยเชิงพรรณนาแบบตัดขวางร่วมกับการวิจัยเชิงปฏิบัติการ มีวัตถุประสงค์เพื่อศึกษาพฤติกรรมการขับขี่รถจักรยานยนต์และการมีส่วนร่วมในการป้องกันแก้ไขปัญหาอุบัติเหตุที่เกิดจากรถจักรยานยนต์บนท้องถนน ในการศึกษาครั้งนี้ผู้วิจัยแบ่งการนำเสนอข้อมูลเป็น 2 ส่วน คือ ข้อมูลเชิงปริมาณ ได้จากการศึกษาวิจัยเชิงพรรณนาและข้อมูลเชิงคุณภาพ ได้จากการศึกษาวิจัยเชิงปฏิบัติการในการสำรวจพฤติกรรมการขับขี่รถจักรยานยนต์ เก็บรวบรวมข้อมูลโดยใช้แบบสัมภาษณ์ในประชาชน จำนวนทั้งสิ้น 404 คน ส่วนการศึกษาการมีส่วนร่วมของประชาชนในการป้องกันและแก้ไขปัญหาอุบัติเหตุที่เกิดจากรถจักรยานยนต์บนท้องถนน เก็บรวบรวมข้อมูลจากประชาชนที่เข้าร่วมโครงการ จำนวน 122 คน โดยใช้วิธีการสนทนากลุ่ม สัมภาษณ์เจาะลึก การสังเกต และการถอดบทเรียนจากเวทีประชาคม ตรวจสอบข้อมูลด้วยวิธีสามเส้า วิเคราะห์ข้อมูลจากความสอดคล้องเชิงเนื้อหา ผลการศึกษาสัดส่วนประสบการณ์การเกิดอุบัติเหตุของกลุ่มตัวอย่าง จำนวน 404 คน พบกลุ่มตัวอย่างที่เคยประสบอุบัติเหตุ ร้อยละ 37.6 (95% CI: 31.1–44.0) เป็นเพศชาย ร้อยละ 33.3 (95% CI: 26.5–40.1) เป็นเพศหญิง กลุ่มที่เคยประสบอุบัติเหตุมีคะแนนความรู้เกี่ยวกับกฎหมายจราจรเฉลี่ย 6.2 (95%CI: 6.00–6.4) มีคะแนนเฉลี่ยด้านการขับขี่ปลอดภัย 6.7 (95% CI: 6.52–6.94) ด้านสภาพแวดล้อมในการขับขี่รถจักรยานยนต์ พบมีบริเวณถนนที่มีป้ายเตือน/ป้ายห้าม ร้อยละ 80.5 สัญญาณไฟจราจรเสียบ่อย ร้อยละ 50.6 กลุ่มตัวอย่างที่เคยประสบอุบัติเหตุ สวมหมวกนิรภัยทุกครั้งขณะขับขี่ ร้อยละ 42.8 ปรับแต่งรถจักรยานยนต์ โดยปาดเบาะ ร้อยละ 32 เคยดื่มสุราแล้วขับขี่รถจักรยานยนต์ ร้อยละ 36.9 เคยขับรถฝ่าสัญญาณไฟจราจร ร้อยละ 40.2 ขับขี่รถจักรยานยนต์โดยใช้ความเร็วในช่วงความเร็ว 51-80 km/hr ร้อยละ 69.4 ขับรถโดยไม่พกใบอนุญาตขับขี่ ร้อยละ 80.5 ใช้โทรศัพท์เคลื่อนที่ขณะขับขี่ ร้อยละ 52.0 เทคนิค AIC ใช้ในการศึกษาการมีส่วนร่วมในการป้องกันและแก้ไขปัญหาอุบัติเหตุบนท้องถนนจากรถจักรยานยนต์พบว่า ปัจจัยที่ส่งผลให้เกิดอุบัติเหตุในเขตพื้นที่ตำบลท่ามิหรำ มี 3 ปัจจัย คือ คน รถ และสิ่งแวดล้อม โดยปัจจัยที่สำคัญที่สุดคือ คนไม่เคารพกฎหมายจราจร จากการศึกษาได้พบปัญหาและแนวทางในการแก้ไขปัญหา ได้แก่ ไม่สวมหมวกนิรภัยขณะขับขี่รถจักรยานยนต์ แนวทางแก้ไขคือ ต้องเลือกขนาดของหมวกนิรภัยให้พอดีกับศีรษะของตนเอง และที่สำคัญควรใช้หมวกนิรภัยที่ได้มาตรฐานที่มีเครื่องหมาย มอก. รับรอง ดื่มสุราจนเมาแล้วขับขี่รถจักรยานยนต์แนวทางในการแก้ไข ต้องสร้างจิตสำนึกให้กับประชาชนกลุ่มดังกล่าว ให้มีการรณรงค์สร้างค่านิยมไม่ให้ดื่มสุรา ขับรถโดยไม่มีใบอนุญาตขับขี่ ผู้บังคับใช้กฎหมายต้องมีความพยายามที่จะบังคับใช้กฎหมายให้เข้มงวดมากขึ้นคำสำคัญ: พฤติกรรมการขับขี่รถจักรยานยนต์ การมีส่วนร่วมในการป้องกันและแก้ไขปัญหาอุบัติเหตุThis is a cross-sectional descriptive and action research. The purpose of the study was to examine the behaviors of riding motorcycles and the participation in preventing and solving the problems of road accidents resulting from riding motorcycles. The data was presented in two parts which were quantitative data received from the descriptive research and qualitative data acquired from the action research. The data in the survey of the behaviors of riding motorcycles was collected from 404 participants using the interview. Furthermore, the data in the part of the participation in preventing and solving the problems of road accidents resulting from riding motorcycles was collected from 122 participants joining the project using group discussion, in-depth interview, observation and lesson distilled from civil society forums. The data was tested using triangulation method and analyzed with the credibility of the data. The results of the study were as follows. 37.6 percent (95% CI: 31.1-44.0) of 404 participants who had ever experienced the accident were male while 33.3 percent (95% CI: 26.5–40.1) of the participants were female. The average scores of their knowledge about traffic laws and riding safely were 6.2 (95% CI: 6.00-6.4) and 6.7 percent (95% CI: 6.52-6.94) respectively. In the aspect of circumstances in riding motorcycles, there were 80.5 percent of warning and banning signs, and 50.6 percent of frequently-broken traffic lights. 42.8 percent of the participants who had ever had the accident wore helmets every time they were riding motorcycles. 32 percent modified and decorated their motorcycles by slicing off their motorcycle seats. 36.9 percent were drunk while riding motorcycles. 40.2 percent had ever ridden through the red light. 69.4 percent rode the motorcycles with the speed of 51-80 km/hr. 80.5 percent rode their motorcycles without bringing their motorbike riding licenses. 52 percent used mobile phones while riding motorcycles. AIC technique used to study participating in preventing and solving the problems of road accidents resulting. After the projects, it was found that there were 3 factors causing accidents in Tamirum which were motorcycle riders, motorcycles and circumstances. The most essential factor was that riders did not respect traffic laws. According to the study, the problems and the ways to solve the problems were as followings. The solution of solving the problem of not wearing helmet while riding motorcycles was to choose the appropriate sizes of the helmets for the riders’ heads and the standard of helmets should meet Thai Industrial Standards Institute. The riders who were drunk while riding must be taught to raise their awareness by constructing the value of not drinking alcohol. Riding motorcycle with no motorbike riding licenses could be solved by having more strict regulations.Keywords: Behaviors of riding motorcycles, Participating in preventing and solving acciden

Impregnation of Natural Rubber into Rubber Wood: A Green Wood Composite

A green wood composite material was developed from the two environmentally friendly substrates natural rubber (cis-1,4-polyisoprene) and rubber wood (Hevea brasiliensis). Natural rubber (NR) was introduced into rubber wood by pressurization of NR latex, followed by the removal of the aqueous phase to allow only dry NR to remain inside the wood structure. Scanning electron microscopy images and the weight increase of the dry impregnated samples revealed the retention of dry NR within the rubber wood. The natural rubber enhanced the water resistance and compressive strength of the treated rubber wood

Water Swollen Natural Rubber

Modification of natural rubber by grafting of maleic anhydride yielded a water absorbable substrate. It was found that water contact angles of treated samples declined as the concentrations of maleic anhydride increased reflecting higher water compatibility in grafted samples. Submergence in water of these samples caused dramatic swelling with the water content up to about 60 wt %