| Nitrile rubber which is a kind of polar crystals of unsaturated rubber with good oil resistance, are widely used in automotive, aerospace, petrochemical, textile, wires and cables, printing and other fields, but its itself also has low strength, low modulus, heat resistance shortcomings such as defects. With the continuous development of industrial technology, the oil resistant rubber especially NBR requirements are more demanding, promote the nitrile reinforced modification research. Calcium carbonate whisker has the characteristics of high modulus, high strength, is a kind of green environmental protection, the reinforcing material of cheap; PVC is a kind of plastic with excellent performance and good compatibility with NBR. Through the two aspects of reinforcing filler and rubber blend of nitrile rubber reinforcing modification, has important theoretical and practical significance.In this paper, the preparation of calcium carbonate whisker was modified by sodium stearate surface treatment agent. Study on the effect of surface modifier, modified temperature and time on the surface properties of calcium carbonate whisker. The modification effect was analyzed by XRD, IR spectrum analysis, activation index and deposition volume. The results showed that when the amount of modifier was 2.5%, the modified time was 70 min, and the modified temperature was 70?, The activation index of calcium carbonate whiskers increased from 32.1% to 82.2%, and the crystal lattice was not destroyed, which showed that the modification was successful and the effect was good.The modified calcium carbonate whisker and PVC with NBR made by mixing sulfide composites, study two kinds of material of NBR reinforcing effect. The experimental results show that with the increase of modified calcium carbonate whisker, the physical properties and heat resistance of NBR are significantly improved. When the dosage of modified calcium carbonate whisker was 10 g, the reinforcing effect was the best, Compared with NBR without whiskers, The tensile strength and tear strength increased by 22.6% and 14.7%, and the hardness increased by 3.9%, and the wear ratio decreased by 17.2%; The initial decomposition temperature and the temperature at which the maximum decomposition rate increased 5? and 4 ? respectively, Completely decomposed quality retention increased by 8.7%. PVC for the improvement of the strength and abrasion resistance of NBR has significant effect. The performance of nitrile rubber when adding 15 g PVC compared to not add, the elongation at break decreases due to the increase of rigidity. The initial decomposition temperature and the temperature at which the maximum decomposition rate reduced 1? and 5? respectively, but the quality keep rate of 800? has increased. When Calcium carbonate whisker and PVC reinforced NBR together, the comprehensive performance of composite materials is best. Compared with no added, The tensile strength and tear strength of CaCO3 whisker /PVC/NBR composites increased by 37.4% and 31.6% respectively, the hardness increased by 10.2% and wear ratio decreased by 24%, the quality keep rate of 800? reached 52.52%, heat resistance is well.Oil resistance test showed that adding calcium carbonate whisker and PVC, The maximum strength retention rate of NBR increased from 64% to 64%, the quality rate reduced to 8% from 33% before and after oiled, It can be seen that the addition of calcium carbonate whisker and PVC not only improves the heat resistance of NBR mechanical properties, but also is beneficial to its oil resistance. |
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