Talc-filled composites

Numerous filler characteristics influence the properties of composites [14,15]. Chemical composition and, in particular, purity of the filler both have a direct and an indirect effect on its application possibilities and performance. Traces of heavy-metal contamination decrease stability. Insufficient purity leads to discoloration, high purity CaC03 has the advantage of a white color, while the grey shade of talc filled composites excludes them from some fields of application. 

Figure 7 shows the effect of filler particle shape on the viscosity of filled polypropylene melts, containing glass beads and talc particles, of similar density, loading and particle size distribution. The greater viscosity of the talc-filled composition was attributed to increased contact and surface interaction between these irregularly shaped particles. 

The fatigue resistance of nano- and microcomposites was also compared by Mallick and co-workers [46,56]. In particular, th performed stress-controlled tension-tension fatigue tests on PP nanocomposites reinforced with 5 wt% of organoclay and on 40 wt% talc-filled PP. As reported in Figure 9.15, the S-N diagram of nanocomposites was slightly better than that of neat PP and much higher than that of talc-filled composites. 

Figure 14.19. Crystallization temperature of talc filled PP vs. UV exposure time. [Adapted, by permission, from Rabello M S, White J R, Polym. Composites, 17. No.5,1996, 691-704.]...

Audrey, W., Rahul, B., Amar, K.M. Novel talc-filled biodegradable bacterial polyester composites. Ind. Eng. Chem. Res. 45, 7497-7503 (2006)... 

Ariffin, A., Mansor, A.S., Ariff, Z. M., Jikan, S.S., Ishak, Z.A.M. (2008). Effect of filler treatments on rheological behaviour of calcium carbonate and talc-filled polypropylene hybrid composites /. Appl. Polym. Sci, 108, 3901-3916... 

Hattotuwa, G.B. Premalal Ismail, H. Baharin, A. (2002). Comparison of the Mechanical Properties of Rice Husk Powder Filled Polypropylene Composites with Talc Filled Polypropylene Composites. Polymer Testing, Vol.21, No.7, (n. d. 2002), p>p. 833-839, ISSN 0142-9418... 

H.G.B. Premlal, H. Ismail, and A.A. Baharin, Comparison of the mechanical properties of rice husk powder filled polypropylene composites with talc filled polypropylene composites. Polym. Test. 21(7), 833-839, (2002). 

The size of the crushed ore can be further reduced using roller mills or cone crushers. The requirements of the talc-plastic composite determine the fineness of the talc. A standard grinder roller produces 50 pm particles, finer grades are between 10 and 40pm, and the finest grades are between 3 and 10 pm [2]. Roller-milled products are used in low impact strength polymer-filled parts, such as fans in automotive under-the-hood applications. Fine micronization (1-12 pm) is carried... 

Noble Polymers supplies a 6% nanoclay-PP composite for the structural seat back of the Honda Accura TL 2004 car. It replaces a 30% glass PP compound in the seat back. Noble Polymers is also targeting the replacement of 20% glass fibre reinforced PP in office furniture parts. Southern Clay Products supplies Cloisite nanocomposite external parts to General Motors for its Impala vehicle, in competition with talc-filled PP. 

Trantina (3) analyzed the creep behavior of talc-filled polypropylene composites under constant uniaxial stress loads. He proposed a general expression for the strain ec attributed to creep alone as a superposition of time (f), stress (a), and temperature (T) dependence. The model equation is written as a product of three separate functions for each parameter ... 

Polypropylene composites have many advantages over metal such as corrosion resistance, low weight, easily molded complicated shapes, and low cost. A 1979 article (1), compared the cost of polypropylene composites versus steel sheet at equal stiffness (Table 14.1). Mica-filled (40 wt%) polypropylene was the only composite with a relative cost less than that of steel (0.98) for a part with stiffness equal to steel. The relative thickness of the composite was 2.88 and the relative weight was 0.45. Cost calculations were based on mica at 0.18/ lb and polypropylene at 0.31/lb. The relative cost of a 40% glass-filled polypropylene composite was 2.48 and its relative weight was 0.49. The relative cost of a 40 wt% filled talc/polypropylene composite was 1.32 and the relative weight was 0.61. 

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]. 

Yua Sheng et al. [153] and Leong et al. [155] measured the tensile, flexural, and impact properties of ultra-fine-talc-filled polypropylene composites. Experimental results indicated that the addition of talc inflnenced the crystallization, morphology, and mechanical properties of talc-polypropylene composites. When the talc content was increased from 0% to 25%, the crystallinity of the polypropylene phase reached a maximnm at 15% talc and the tensile and flexural strengths of talc-polypropylene composites also attained a maximum, while the impact strength declined to its lowest level. Scanning electron microscopy photographs of impact... 

Saq an et al. [106] determined the physical properties of a talc-filled polypropylene composite. Measurements included volume resistivity, electrical conductivity, and volume resistivity. The effect of talc content and temperature on the thermal, elastic, and electrical properties of the polymer was studied. 

S.-Y. Lee, I.-A. Kang, G.-H. Doh, H.-G. Yoon, B.-D. Park, and Q. Wu, Thermal and mechanical properties of wood flour/talc-filled polylactic acid composites Effect of filler content and coupling treatment. J. Thermoplastic Compos. Mater. 21,209 (2008). 

Figure 1 Modulus of RHA composites as a function of filler loading. NS, FUMED and PP/talc represents Neuberg Silica, fumed silica and talc-filled polypropylene...

Huda et al. [31] evaluated the flexural and impact properties of PLA/recycled newspaper cellulose fiber (RNCF 30 wt%)/talc (10 wt%]. The flexural and impact strength of these hybrid composites were reported to be significantly higher than that made from either PLA or RNCF. The hybrid composites showed improved flexural strength of 132 MPa and flexural modulus of 15.3 GPa, while the unhybridized PLA-/RNCF-based composites exhibited flexural strength and modulus values of 77 MPa and 6.7 GPa, respectively. SEM micrographs of the fracture surface of notched izod impact specimen of 10 wt% talc-filled PLA/RNCF composites showed good filler particle dispersion in the matrix. 

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