Molds manufacturing to produce chloroprene rubber product with carbon steel over time the mold surface will wear. From the original. The practice in the industry often uses surface coatings (Hard chrome method) or change materials to create molds. Therefore this research is to study the effect of corrosion or wear. To see the size of surface mold changed in the experiment. Based on a tolerance of 0.1 millimeters at the molding point and after molding in the actual work conditions of a 2-3 weeks sample and mold size measurement. At less than 10 times the permissible coordinate value is 0.01 millimeters. The experiment found that. The wear of carbon steel molds was formed with chloroprene rubber. It has a very small value when referenced to the tolerance coordinates which is not significantly reduced when the rubber specimen size is determined. The allowance range is 10 μm to 100 μm. Therefore the design of chloroprene rubber to make molds with carbon steel. It can help reduce production costs. Without replacing with corrosion-resistant materials or adding coatings.

The objectives of this research are to propose an efficient and proper model that fits the cassava and rubber yields data. A generalized estimating equation (GEE) and a linear mixed model (LMM) with spatial correlation following the conditional autoregressive model (CAR) were adopted. The dependent variables are the cassava and rubber yields collected each month in every province of Thailand. The factors considered are rainfall averaged temperatures and regions. The results from GEE and LMM show that the factors influencing on the cassava and rubber yields are rainfall averaged temperature and region. Both GEE and LMM fit the correlated data. The GEE is used to explain the influence of factors on the yields in all provinces while the LMM is used to explain the influence of factors on the yields in each province.

This continued 2nd year researchaims to study the development of the para rubber press machine with wrought pattern for continued 2nd-year. Used natural para rubber mixed in a Ta-kuong by normally practical para rubber farmer style to evaluate the rubber press machine. A machine consists of the 11 roller sets in vertical pathway with press sticks on top. The components are as follows: a water press roller with a slope surface to reduce the diameter around 1-1.5 mm from a center the 3-pair sets of normal press rollers and the 2 duo sets of wrought pattern rubber press rollers with the induction motor at 1430 rpm. The rotating transmission based on belts and chains with a . The evaluated results produced the dried para rubber sheets thickness at 3.79 mm on average as the 2nd rubber sheet type standardin marketing need. From a top tray a farmer can put a sticky para rubber piece to a roller press machine easier than normal just 5.9 second on average with lower hand power to handler of the rubber pieces. In finally the wrought patternrubber sheets by a worker to carry the ta-kuong to a top tray of a rubber press machine and a rubber press man to put the para rubber pieces to a machine thus the completed 186 wrought rubber sheets per hour on average.

This research presents the engineering properties of asphalt (AC 60/70) modified with different ratios of scrap natural rubber. Then select the best properties of the binder to mix asphaltic concrete. From laboratory testing results with adding 7% scrap natural rubber into mixtures for the best results. The properties of asphaltic concrete can be improved by adding 7% scrap natural rubber. For asphaltic concrete Marshall Stability increased with adding scrap natural rubber into asphalt. Moreover the stiffness modulus of asphaltic concrete can be improved 13.53 compared to AC 60/70.

The aims of this research work were to enhance the impact resistance and processibilty of wheat gluten (WG) by the addition of epoxidized natural rubber (ENR) compared to glycerol. This work was divided into two parts: to study the optimum ENR content for improvement of WG and the effect of together functions between ENR and glycerol on the properties of WG. Tested specimens were mixed and prepared by internal mixer and compression molding machine respectively. ENR and glycerol were varied from 10 to 40 phr. The effects of modifier types and contents on WG were evaluated by tensile impact and water absorption testing and thermal analysis. Fracture behavior and rubber dispersion were investigate with scanning electron microscope (SEM). The result revealed that the increase of ENR or Glycerol contents led to the decreases in tensile modulus and strength except for modifier content of 10 phr whereas elongation at break and impact strength increased. Glass transition temperature (Tg) of modified WG tended to decreased with the increase of ENR or glycerol contents especially for glycerol. The presence of glycerol affected on the decomposition temperature (Td) values but those were unchanged for case of ENR. Water resistant of WG specimen was improved by the presence of ENR whereas the increase of glycerol led to weight loss at immersion time of 2880 min. For the effect of ENR : glycerol ratios it indicated that glycerol enhanced tensile resistances but suppressed impact and water resistances of modified WG by ENR. Sizes and dispersion of ENR particles were improved by the addition of glycerol. Tg and Td values of modified WG by ENR and glycerol increased when ENR fractions were increased.