This paper mainly discusses the effect of coupling on the tensile properties of glass fiber (GF)/carbon fiber (CF) reinforced polypropylene (PP) hybrid composites which were made through a new injection molding process named direct fiber feeding injection (DFFIM) process. It is mainly divided into two parts which discusses the functional of coupling agent in the composites system, and the different contents of coupling agent (PA6 and MAPP) on the tensile properties of composites. DFFIM progress is a new method that by directly feeding of continuous carbon fiber into the barrel of injection molding machine to make the hybrid composites. The continuous CF roving strands are guided into the vent of devolatilizing unit of injection barrel and fed into the melt by the shearing motion of the screw during plasticization process. By using DFFIM process to make composites, the fiber attrition during extrusion compounding will be eliminated. It is a great improvement in reduction of material cost. And also the cost of reinforcing compounded pellet in the traditional composites market value chain could be lower. Polyamide 6 (PA6), Maleic anhydride-grafted polypropylene (MAPP) or both of them were mixed with pellets during the DFFIM process and PA6 and MAPP were used as coupling agent for CF/GF reinforced PP system. The CF and GF contents in each hybrid composites were tested to analysis the influence of fiber contains on the tensile properties of composites. Usually, better interfacial bonding between fiber and matrix in composites, better tensile properties of composites. So the effect of coupling agent (PA6 and MAPP) on the interfacial bonding between CF and PP in hybrid composites were firstly analyzed. And then the influence different contents of PA6 and MAPP on the tensile properties of GF/PP composites and GF/CF reinforced PP hybrid composites were investigated. It is found that the addition of PA6 did not improve the interfacial bonding but the addition of MAPP has shown a little improvement to the bonding between CF and PP. And when using PA6 and MAPP together as co-coupling agent, the tensile properties of composites has greatly increased. And, there is fiber aggregation in the core layer of the hybrid composites which made by DFFIM process, while there is no such phenomenon happened in the condition of normal injection molding process. It is the main reason that the tensile strength of hybrid composites without coupling agent is weaker than the GF/PP composites. And the tensile modulus of composites would be increased considerably. That is due to the addition of the carbon fiber which has high tensile modulus. In the condition of composites with 1wt.% PA6, the 1wt.% PA6 shows positives effect on tensile properties and while PA6 has negative role when the amount of PA6 has improved. Within a certain range, the larger amount of MAPP in the system of MAPP-PA6 composites, the better on the tensile properties of composites is. And MAPP has positive effect on the tensile properties of composites.

The direct fiber feeding injection molding (DFFIM) process is the new fabrication technique. This technique is able to eliminate the compounding process. In this study, the composite consisting of glass fiber/carbon fiber/ABS (GF/CF/ABS) were fabricated. Tensile, bending and Izod impact test were conducted to compare mechanical properties between glass fiber and glass fiber/carbon fiber hybrid composites. The additional of carbon fiber improved tensile, bending and impact properties of the hybrid composites. SEM photographs indicated that carbon fiber tended to agglomerate during DFFIM process. It can be noted that the low content of carbon fiber was suitable for enhanced mechanical performances of GF/CF/ABS hybrid composites.

. In this study, characteristics of glass fiber reinforced recycled-PET composites by using direct fiber feeding injection molding (DFFIM) process were studied. The results, when varied processing conditions, indicated that decreasing of matrix feeding screw speed and increasing of number of glass fiber led to the increasing of fiber loading content, respectively. The average fiber length of glass fiber tended to decrease with the increasing of fiber loading content. Tensile modulus and tensile strength exhibited almost linear correlation with glass fiber load content. For study on stability of DFFIM process performance, at earliest stage of DFFIM process, discarding of at least five injected shots must be done in order to prepare the system availability of DFFIM process. The DFFIM machine could uninterruptedly manufacture composites without any problems occurred during 7 hours, which consequently provided high stability of product quality with long-term fabrication.

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In Japan, the production of traditional handmade Japanese paper using the spring water has been performed in the Shuso area of Shikoku Island. However, the method of production was been handed down by trial and error and observation of the expert movement until now. The produced papers are counted one unit that is five hundred sheets of Japanese paper. Five hundred sheets of Japanese paper are called 1 [lot]. The paper has two type of thickness and its size is 600mm × 1500mm. Thick paper is 9[kgf] per lot. The other hand, thin paper is 8[kgf] per lot. In other words, the expert is making paper which is the difference of 2[gf] per sheet. This time, we have been able to obtain cooperation with traditional craftsman for the digitizing of his skills. Therefore, we visualize the tacit knowledge of the expert’s skill. The expert subject has 34 years of experience of traditional hand-made Japanese paper. We have digitized his manufacturing movement by using motion capture. His movements are analyzed by attaching infrared reflective markers of 20 on each parts of the body. In this study, we found that constant rhythm of the neck in handmade Japanese paper manufacturing movement. Furthermore, the first scoop is performed at the time much shorter than in the case of other scoops.