Structure and properties of polypropylene

252 Aliphatic Polyolefins other than Polyethylene, and Diene Rubbers 

Only a limited amount of information is available concerning the effects of molecular weight distribution. There is, however, evidence that the narrower the distribution the more Newtonian are the melt flow properties. It has been noted 

One unfortunate characteristic property of polypropylene is the dominating transition point which occurs at about 0°C with the result that the polymer becomes brittle as this temperature is approached. Even at room temperature the impact strength of some grades leaves something to be desired. Products of improved strength and lower brittle points may be obtained by block copolymerisation of propylene with small amounts (4-15%) of ethylene. Such materials are widely used (known variously as polyallomers or just as propylene copolymers) and are often preferred to the homopolymer in injection moulding and bottle blowing applications. 

Further variations in the properties of polyethylenes may be achieved by incorporating additives. These include rubber, antioxidants and glass fibres and their effects will be discussed further in Section 11.1.4. 

Published data on coi ercial polypropylenes indicate that their molecular weights ar injhe range = 38 000-60000 and Af, = 220000-700000, with values of from about 5.6 to 11.9. These averages are somewhat higher 

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Li, W. H., Chen, X. H., Yang, Z., and Xu, L. S. 2009. Structure and properties of polypropylene-wrapped carbon nanotubes composites. Journal of Applied Polymer Science 113 3809-3814. 

MartusceUi E. (1995) Structure and properties of polypropylene-elastomer blends, in Polypropylene - Structure, Blends and Composites, 1st edn, (ed. J. Karger-Kocsis), Chapman Hall, London, Vol. 2, pp. 95-140. 

Gamma radiation, frequently used for sterilization in diverse medical applications, and for crosslinking of pol3aners, may cause important modifications in both structure and properties of polypropylene (PP) and related copolymers. It was foimd that the radiation resistance of polymers strongly depends on their amorphous or crystalline structure. 

Lin, S. Waymouth, R. M. 2-Arylindene metallocenes ConformationaUy dynamic catalysts to control the structure and properties of polypropylenes. Acc. Chem. Res. 2002, 35, 765-773. 

Khunova V, Kristof J, Kelnar I, Dybal J (2013) The effect of halloysite modification combined with in situ matrix modifications on the structure and properties of polypropylene/halloysite nanocomposites. eXPRESS Polym Lett 7(5) 471-479... 

RK Datta, K Sen, AK Sengupta, RS Gandhi. Influence of mass colouration on structure and properties of polypropylene feeder and draw textured yams. Proc World Textile Congress on Polypropylene in Textiles, Huddersfleld, 1996, pp 231-248. 

Ding C., Jia D., He H., Guo B. and Hong H., How organo-montmorillonite truly affects the structure and properties of polypropylene , Polym Test, 2005, 24,94—100. Usuki A., Kato M., Okada A. and Kurauchi T., Synthesis of polypropylene-clay hybrid , J Appl Polym Sci, 1997, 63, 137-139. 

G. Natta and P. Corradini. Structure and properties of isotactic polypropylene , Nuovo Cimento, Suppl. 15, 40 (1960). 

To get a better insight into the chlorination reaction, we wanted to avoid a heterogeneous process. Instead of polyethylene or polypropylene, we used polyisobutene, which is soluble in carbon tetrachloride, as are its chlorination products. In addition, we were interested in the structure and properties of the chlorinated products, especially in comparison with polyvinyl chloride (PVC) and vinyl chloride/isobutene (VC/IB) copolymers. 

Fujiyama, M., Kitajima, Y. Inata, H. (2002) Structure and properties of injection-molded polypropylenes with different molecular weight distribution and tacticity characteristics. Journal of applied polymer Science. Vol.84 (12), pp.2142-2156... 

Nam P. H. Okamoto M. Kotaka T. Hasegawa N. Usuki, A. A hierarchical structure and properties of intercalated polypropylene/ clay nanocomposites. Polymer, vol.42, (2001), 9633-9640... 

Garbarczyk, J. et al (1989). Influence of additives on the structure and properties of polymers. 4. study of phase-transition in isotactic polypropylene by synchrotron. Polym. Commun., Vol. 30, Issue 5, pp.153-157. 

Nasegawa, H., Okamoto, H., Kawasiuni, M., Hasegawa, N., and Usuki, A. 2001. A hierarchical structure and properties of intercalated polypropylene/clay nanocomposites, h/mer 42 9633-9640. 

Kurokawa, Y, Yasuda, H., Kashiwagi, M., and Oya, A. 1997. Structure and properties of a montmorillonite/polypropylene nanocomposite./oHrjwZ of Materials Science Letters 16 1670-1672. 

Kim, D. H., Fasulo, P. D., Rodgers, W. R, and Paul, D. R. 2007. Effect of the ratio of maleated polypropylene to organoclay on the structure and properties of TPO-based nanocomposites. Part I Morphology and mechanical properties. Polymer 48 5960-5978. 

Chapter 5 summarizes the investigation of lignocellulosic flax fiber-based reinforcement requirements to obtain structural and complex shape polymer composites. This chapter discusses in detail the possibility of forming complex shape structural composites which are highly desirable for advanced applications. Chapter 7 focuses on the structure and properties of cellulose-based starch polymer composites, while Chapter 8 focuses on the spectroscopic analysis of rice husk and wheat gluten husk-based polymer composites using computational chemistry. Chapter 9 summarizes the processing, characterization and properties of oil palm fiber-reinforced polymer composites. In this chapter, the use of oil palm as reinforcement in different polymer matrices such as natural rubber, polypropylene, polyurethane, polyvinyl chloride, polyester, phenol formaldehyde, polystyrene, epoxy and LLDPE is discussed. Chapter 10 also focuses on... 

Kloos F (1987), Dependence of structure and properties of melt spun Polypropylene fibers on molecular weight distribution . Polymer Science Symposium honoring Leo Mandelkern, Florida State University, Tallahassee, FL, 5 September, 1987. 

M Fujiyama. Structures and properties of injection moldings of glass fiber-filled polypropylene. Int Polymer Proc VIII 245-254, 1993. 

Cai LF, Huang XB, Rong MZ, Ruan WH, Zhang MQ (2(X)6) Effect of grafted polymeric foaming agent on the structure and properties of nano-silica/polypropylene composites. Polymer 47(20) 7043-7050... 

Fujiyama, M. (1996) Structure and properties of inflation films of P-phase nucleating agent-added polypropylene. Int. Polymer Process., 11, 159-66. 

Fujiyama, M. (1995) Structures and properties of injection molding of P-crystal nucleator-added polypropylenes. Part 1 Effect of p-crystal nucleator content. Inf. Polymer Process., 10,172-8. 

Sterzynski, T., Lambla, M., Crozier, H. and Thomas, M. (1994) Structure and properties of nucleated random and block copolymers of polypropylene, Adv. Polymer Technol, 13, 25. 

Natta, G. and Corradini, P. (1960) Structure and properties of isotactic polypropylene, Nuovo Cimento Suppl., 15,40-51. 

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