Filled polypropylene

The first difference of normal stresses (tr, t) may serve as an indirect index of the highly elastic properties of polymeric systems [199]. C. D. Han [200] related (ru with the residual pressure at outlet Pt)dt. Han, who observed its reduction in polypropylene filled with calcium carbonate [201], concluded that filling decreases the normal stresses. Note that addition of fibrous fillers, vice versa, somewhat increases Pexi, [180]. 

About 20 years ago, the first industrial development was launched with a polypropylene filled with 50% wood flour. 

Various investigations have considered the effects of titanate treatments on melt rheology of filled thermoplastics [17,41]. Figure 10, for example, shows that with polypropylene filled with 50% by weight of calcium carbonate, the inclusion of isopropyl triisostearoyl titanate dispersion aid decreases melt viscosity but increases first normal stress difference. This suggests that the shear flow of the polymer is promoted by the presence of titanate treatment, and is consistent with the view that these additives provide ineffective coupling between filler particles and polymer matrix [42]. 

Watson, G.L. (1987) A study of the fire and mechanical properties of polypropylenes filled with sea water magnesium hydroxide, PhD thesis, Brunei University, UK... 

To conclude this brief digression into history, we may point out one more important aspect the high efficiency of the combined shear in molding of filled thermoplastics. One of the first works in this field was 31) which described experiments carried out with polypropylene filled with a disperse aggregate calcium carbonate (chalk) and a short-fiber material-asbestos. 

Fig. 11. Pressure/flow-rate characteristics of extruder (capacity versus pressure drop across the head) in processing of polypropylene filled by 10 % (by mass) of chalk (a) and 20 % (by mass) of asbestos (b) at a temperature in the head equal to 210 °C and amplitude of reciprocatingrotary vibration of the core, degr.— 0 2 — 4 3 — 11.5 — 22.3...

Chiu, S.H. and Wang, W.K., Dynamic flame retardancy of polypropylene filled with ammonium polyphosphate, pentaerythritol and melamine additives, Polymer, 39, 1951-1955, 1998. 

Figures 8.51 and 8.52 show differences between the behavior of polypropylene filled with glass beads at different temperatures. In both cases, the debonding between filler and the matrix requires the lowest level of energy and confirms that this is the most likely mode of failure. The volume fraction of filler has little effect on debonding, cavitation, and yielding at 0°C. At -6()°C, yielding is improved by increasing concentration of filler. Debonding is initiated at the poles and begins plastic yielding in the matrix which ultimately leads to failure. Strain required to initiate failure is reduced when the filler concentration is increased. ...

Figure 9.2. Reduced viscosity of polypropylene filled with different grades of calcium carbonate as a function of volume fraction. [Adapted, by permission from Gendron R, Daigneault L E, Tatibouet J, Dumoulin M M, Adv. Polym. Technol., 15, No.2, 1996, 111-25.]...

M Chamoumi, A Crespy, A Benhassaine, A Boukhari, J Aride. Improvement of impact strength of polypropylene filled with latex coated kaolin. Annales de Chimie-Sci Mat 19(7-8) 395-398, 1994. 

Cellulose fiber is a good reinforcing tiller. In fact, this is one of the two major factors of the very existence of WPC materials (a) to make the composite material less expensive and (b) to obtain material with overall better properties compared to neat plastic, on the one hand, and wood, on the other. For example, tensile modulus of a particular sample of neat polypropylene was 203,000 psi, whereas for the same polypropylene filled with 40% of jute it was 1,030,000 psi. For a comparison, for the same polypropylene filled with 40% glass fiber it was 1,100,000 psi. Tensile modulus for natural fiber itself is in the range of 3,800,000-17,400,000 psi [135]. Table 3.4 shows data in more detail. 

Effect of talc on flexural strength and modulus of plastics is often higher compared with that of calcium carbonate. For example, polypropylene filled with 58% CaC03 had flex strength and modulus of 4430 270 and 365,000 44,000 psi, respectively, but the same polypropylene filled with 20% CaCOs and 30% talc had flex strength and modulus of 6125 + 100 and 486000 18000 psi, respectively. 

Unlike WPC, neat polypropylene filled with the same nanoclay significantly increases its flexural strength and modulus (Table 4.30). 

Generally, nanomaterials as flame retardants do not have commercial applications. Data obtained are commonly recognized as preliminary, and they are described here just as preliminary as well. One more example of such data is a study of heat release and char formation (in per cent units) at burning of polypropylene filled with magnesium hydroxide (5 pm, 1 pm particles, and nanoparticles) (Table 14.9). 

Figure 17.7 A comparison of data for a neat polypropyl and the polypropylene filled...

The syringe is usually made out of polypropylene, filled with 100 to 1000 mg of sorbent having a particle size of 30 to 120 /rm, and equipped with frits to contain the packing. 

Some of the asbestos filler in hydraulic cements has been replaced by flbrlllated polypropylene. More than 500 thousand shell piles of this flbrlllated polypropylene-filled Portland cement, called "Carlcrete" are produced annually in England. —... 

The experimental results presented above permit the conclusion that the model presented in the previous sections satisfactorily accounts for the tensile behavior of polypropylene filled with non-adhering filler. The best quantitative agreement between theory and experiment is obtained for the samples with higher volume fractions of the filler which deform in a more homogeneous way. 

Velasco, J.I., Desaja, J.A., Martinez, A.B. Crystallization behavior of polypropylene filled with surface-modified talc. J. Appl. Polym. Sci. 61, 125-132 (1996)... 

In the following Figures 4.58 and 4.59 dependencies of polypropylene filled with nanoparticles on filler content and test temperature are shown. 

Wenyi, W., Xiaofei, Z., Guoquan, W., and Jianfeng, C. 2006. Preparation and properties of polypropylene filled with oreano-montmorillonite nanocomposites. Journal of Applied Polymer Science 100 2875-2880. 

Zhang, H. and Zhang, Z. 2007. Impact behaviour of polypropylene filled with multi-walled carbon nanotubes. European Polymer Journal 43 3197-3207. 

Causin, V., Yang, B. X., Marega, C., Goh, S. H., and Marigo, A. 2009. Nucleation, structure and lamellar morphology of isotactic polypropylene filled with polypropylene-grafted multiwalled carbon nanotubes. European Polymer Journal 45 2155-2163. 

PI 120 Polypropylene filled with mineral and glass, PP MA Industries... 

Polyfort Polypropylene filled with mineral, glass, PP A Schulman bic. 

Interesting results were reported by Mi et al. [19]. They analyzed polypropylene filled with bamboo fibers with the addition of polypropylene grafted with maleic anhydride. The use of the agent promoting the adhesion was aimed at improving interactions between the components. In case of systems polypropylene/bamboo fibers/compatibilizer, the TCL has been formed. This was explained by higher ability to nucleation of bamboo fibers in relation to MAPP-grafted polypropylene as compared to pure polymeric matrix. 

Haworth, B. and Raymond, C.L. (1997) Processing and fracture characterisation of polypropylene filled with surface modified calcium carbonate. Proceedings of the Eurofillers 97 Conference, Manchester, UK, September 1997,... 

Table 15.5 Mechanical properties of composites made from polypropylene filled with 40 wt% wood flour [38]. 

Figure 21.4 Flexural modulus comparison for foamed and unfoamed polypropylene filled with wood flour (PPW 20, 30, 40, and 50%). Foaming with 3.25% Expancel 092 MB 120.

The CNIS and of a group of ternary composites of polypropylene filled with 30 vol% of rigid Mg(OH)2 and 10 vol% of elastomeric EPR inclusions were studied as a function of a concentration of maleic anhydride (MAH). In all systems studied, the variation in adhesion was achieved by increasing the concentration of MAH in either the matrix (complete separation of the elastomer and filler) or in the elastomer (complete encapsulation of the filler by the elastomer). The CNIS/Gc ratio and scale factor are plotted versus MAH concentration in Fig. 6.13,a and b, respectively. 

Studies have also been condncted on the effect on mechanical properties of polypropylene filled with talc [22]. 

Boudenne Abderrahim, Ibos Laurent, Fois Maura, Majeste Jean Charles, and Gehin Eveline. Electrical and thermal behavior of polypropylene filled with copper particles. Composites Part A. 36 no. 11 (2005) 1545-1554. 

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