Tham khảo tài liệu 'contemporary robotics - challenges and solutions part 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Prospective polymer composite materials for applications in flexible tactile sensors 111 sandpapered brass foil mould inserts were used on both sides of the samples. The previous research approved them to be the most suitable for this need because brass forms permanent electro-conductive bonding with the PHSCNC during vulcanization. To provide optimal processing parameters first the optimal complete curing time of the composite was ensured using MonsantoRheometer100 rubber rheometer and appeared to be 40 minutes for current rubber composition. Disk shape PHSCNC samples 18mm in diameter Figure 2 with 9 and 10 mass parts of filler were made using different curing times in range from 1 to 40 minutes. 40 minutes corresponds to complete vulcanization of PHSCNC and 1 minute was the smallest possible time to obtain the desired shape of the sample. During pre-research the original method was developed to measure samples initial electrical resistivity in-situ in the curing mould. The results claimed that electrical resistivity of PHSCNC dramatically drops exactly during the vulcanization Figure 3 . This fact made us to assume that the development of percolative electrocondutive structure of filler nanoparticles is happening during the vulcanisation although. 0 100 200 300 400 500 600 t s Fig. 3. The change of specific electrical resistivity black and temperature red as a function of time for PHSCNC sample with 9 mass parts of carbon. 112 CONTEMPORARY ROBOTICS - Challenges and Solutions 70 60 50 40 30 20 10 0 -10 ----1min ----2min ----3min ----4min ----5min ----10min ----15min ----20min ----35min ----40min P bar Fig. 4. The piezoresistance of PHSCNC samples with 10 mass parts of carbon black which are made using different curing times from 1 to 40 minutes. The piezoresistive properties of PHSCNC samples were determined using Zwick Roell universal material testing machine equipped with HBM 1kN load cell and HBM Spider8 data acquisition module. .
