Carbon black-filled block copolymer

DIE EXTRUSION BEHAVIOR OF CARBON BLACK-FILLED BLOCK COPOLYMER THERMOPLASTIC ELASTOMERS... 

CARBON BLACK-FILLED BLOCK COPOLYMER THERMOPLASTIC ELASTOMER SYSTEMS, 714 Fundamentals for Black-Filled Systems, 714 Experimental, 715 Rheology, 716... 

Electrical conductivity measurements have been reported on a wide range of polymers including carbon nanofibre reinforced HOPE [52], carbon black filled LDPE-ethylene methyl acrylate composites [28], carbon black filled HDPE [53], carbon black reinforced PP [27], talc filled PP [54], copper particle modified epoxy resins [55], epoxy and epoxy-haematite nanorod composites [56], polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA) blends [57], polyacrylonitrile based carbon fibre/PC composites [58], PC/MnCli composite films [59], titanocene polyester derivatives of terephthalic acid [60], lithium trifluoromethane sulfonamide doped PS-block-polyethylene oxide (PEO) copolymers [61], boron containing PVA derived ceramic organic semiconductors [62], sodium lanthanum tetrafluoride complexed with PEO [63], PC, acrylonitrile butadiene [64], blends of polyethylene dioxythiophene/ polystyrene sulfonate, PVC and PEO [65], EVA copolymer/carbon fibre conductive composites [66], carbon nanofibre modified thermotropic liquid crystalline polymers [67], PPY [68], PPY/PP/montmorillonite composites [69], carbon fibre reinforced PDMS-PPY composites [29], PANI [70], epoxy resin/PANI dodecylbenzene sulfonic acid blends [71], PANI/PA 6,6 composites [72], carbon fibre EVA composites [66], HDPE carbon fibre nanocomposites [52] and PPS [73]. 

Improvement of the mechanical properties of elastomers is usually reached by their reinforcement with fillers. Traditionally, carbon black, silica, metal oxides, some salts and rigid polymers are used. The elastic modulus, tensile strength, and swelling resistence are well increased by such reinforcement. A new approach is based on block copolymerization yielding thermoelastoplastics, i.e. block copolymers with soft (rubbery) and hard (plastic) blocks. The mutual feature of filled rubbers and the thermoelastoplastics is their heterogeneous structure u0). 

Chiu, H.-T. Chiu, W.-M. The toughening behavior in propylene-ethylene block copolymer filled with carbon black and styrene-ethylene butylene-styrene triblock copolymer. Mater. Chem. Phys. 56, 108-115 (1998). 

Carbon black is the most extensively used filler in terms of volume in thermoplastic/ thermoset elastomers. One method of quantifying carbon black dispersion is through the reduction in resistivity of insulating polymer matrices that occurs by virtue of the CB s ability to create a conductive three-dimensional particulate network. As the amount of carbon black is increased, the resistivity is decreased. In addition, the efficiency of a fixed amount of carbon black is increased as a result of the increased dispersion offered by the use of titanates. As an example. Table 5.8 shows the effect of increasing amounts of LICA 09 on the resistivity of a CB-filled styrene/butadiene block copolymer. 

Unfortunately, for block copolymer thermoplastic elastomers, any trials to accommodate the viscosity changes by carbon blacks into theoretical considerations, or to fit the equations cited onto the rheological behavior of black-filled systems have not been conducted up to now. Of course, such trials will be relatively complex and time-consuming work because thermoplastic elastomer shows intricate properties due to its unique microstructure. 

The main objective of this chapter was to cover the die extrusion behavior of block copolymer thermoplastic elastomers filled with carbon black. Thus, shear... 

---