The Influence Of Lignin And Inorganic Compound On The Compression Set Of Nitrile Rubber

In this thesis, the preparation of lignin and inorganic filler composite and application in nitrile rubber was studied. Organic-inorganic composite filler was obtained by wet milling blend with Lignin and inorganic filler, and was added into nitrile rubber by mechanical wet blending to prepare nitrile rubber composites.Lignin-CaCO₃ composites, lignin-montmorillonite（Lignin-MMT） composites and Lignin-CaSO₄ composites were prepared by wet blending and ball milling.Lignin-CaCO₃/NBR composites was prepared by melt blending. In this study, when the loading of filler was added less than 10 parts, the influence of Lignin and calcium carbonate on mechanical properties of nitrile rubber composites had a simple additive between them, and when the loading of filler reached 20 parts, it didn’t meet the additivity. The compression set of the vulcanizates with complex fillers was significantly smaller than the average compression set of the vulcanizates with only Lignin or CaCO₃. SEM figure showed that lignin was added to promote dispersion of calcium carbonate, and reduced reuniting among the same filler particles. With the reduction of lignin in the filler, the tensile strength and elongation at break of the vulcanized nitrile rubber reduced, and modulus at 100% and hardness increased, compression set of vulcanized rubber filled with lignin and calcium carbonate was less than that filled with only one kind of the fillers.Lignin-MMT/NBR composites was prepared by melt blending. The SEM figure showed that lignin could promote dispersion of montmorillonite, and reduce the formation of montmorillonite agglomeration, the results of DMA indicated that the glass transition temperature of the composites decreased. When the amount of lignin decreaced, the tensile strength of vulcanized rubber, modulus at 100% and hardness increased, elongation at break decreaced. The compression set of nitrile rubber composites with lignin and montmorillonite was in the middle of that in single packing. When the mass ratio of Lignin and MMT was 1:1, with the amount of filler compound increased, the tensile strength, elongation at break and compression set of Nitrile rubber composites increased, modulus at 100% and Shaw hardness decreased.Lignin-CaSO₄/NBR composites was prepared by melt blending. SEM showed that Lignin improved the dispersion of calcium sulfate in nitrile rubber matrix. With the reduction in the proportion of Lignin, the tensile strength and elongation at break of the vulcanized rubber reduced, modulus at 100% and hardness increased. The compression set of Nitrile rubber composites with Lignin and montmorillonite was lower than that in single filler. When mass ratio of Lignin and CaSO₄ was 1:1, with the increase in the amount of filler composites, the tensile strength, elongation at break and compression set of Nitrile rubber composites increased, and modulus at 100% and Shaw hardness decreased.