Isotactic polypropylene/poly blends

Finally, poly(a-PIN) was used in the nonisothermal crystallization of isotactic polypropylene from blends containing up to 30 per cent of this polyterpene [110-112]. 

Yi X, Xu L, Wang Y L, Zhong G J, Ji X and Li Z M (2010) Morphology and properties of isotactic polypropylene/poly(ethylene terephthalate) in situ microfibrillar reinforced blends Influence of viscosity ratio, Eur Polym J 46 719-730. 

Thermal and Structural Characterization of Binary and Ternary Blends Based on Isotactic Polypropylene, Isotactic Poly(l-Butene) and Hydrogenated Oligo (Cyclopentadiene)... 

Three different series of binary blends were prepared by mixing hydrogenated oligo (cyclopentadiene) (HOCP), isotactic polypropylene (iPP), and poly(l-butene) (PB-1), alternatively. The influence of the presence of HOCP, on the morphology, crystallization, melting behavior, and supermolecular structure of... 

In this and the following two sections we consider the data for a PLC and for different blends of that PLC with isotactic polypropylene (PP). The PLC used in this study was liquid crystalline copolyester PET/0.6PHB, where PET = poly (ethylene terephthalate), PHB = p-hydroxybenzoic acid and 0.6 is the mole fraction of PHB in the copolymer, manufactured by Unitika Ltd, Kyoto, Japan. The content of the PLC in the blends with PP was varied from 0 to 20 wt%. The samples were prepared by injection molding. PP, resin VB65 llB, was supplied by Neste OY, Finland. 

Di Lorenzo M.L., Cimmino S., Silvestre C., Nonisothermtil crysteillization of isotactic polypropylene blended with poly(alpha-pinene). 2. Growth rates. Macromolecules, 33(10), 2000,3828-3832. 

In general, silane-coupling agent is used to modify the surface of nanoparticles to enhance the compatibility of nanoparticles and polymers and to improve the mechanical properties of the resulting nanocomposites. The results of melt blending are often ideal. Bikiaris et al. [138] studied the better dispersion of silica in isotactic polypropylene (iPP) matrix by adding poly(propylene-gra/t-maleic anhydride) copolymer (PP-g-MA) containing 0.6 wt% maleic anhydride as compatibility enhancer. This phenomenon could accoimt for the reaction between the maleic... 

Moreover, P3HB shows a crystalline structure because of its stereoregularity similarity to isotactic polypropylene. In order to improve mechanical properties and processability, and thus to obtain a more flexible material, P3HB copolymers are nowadays used. The first attempt to synthesize a random copolymer is a blend of 3-hydroxybutanoic acid and 3-hydroxyvaleric acid, obtaining poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) copolymer. Other blends are obtained using, for example, hydroxyhexanoic acid, 4-hydroxybutanoic acid, and hydroxyoctanoic acid. Physical and mechanical properties of these copolymers have been reported (Lee and Park, 2005, Marchessault and Yu, 2005, Williams and Martin, 2005) as well... 

Discovery of isotactic polypropylene (PP) in 1954 started a search for methods to improve its low-temperature impact strength [1, 2]. These activities commenced in the late 1950s by blending PP with poly-ethylenes (PE) or elastomers, then by copolymerizing it with ethylene into ethylene-propylene rubber (EPR) and ethylene-propylene-diene (EPDM). 

Quan H, Zhong G J, Li Z M, Yang M B, Xie B H and Yang S Y (2005) Morphology and mechanical properties of poly(phenylene sulfide)/isotactic polypropylene in situ microfibrillar blends, Polym Eng Sa 45 1303-1311. 

Zhong G J, Li Z M, Li L B and Mendes E (2007) Crystalline morphology of isotactic polypropylene (iPP) in injection molded poly(ethylene terephthalate) (PET)/iPP microfibrillar blends, Polymer 48 1729-1740. 

Quan H, Li Z M, Yang M B and Lu Z Y (2005) Nonisothermal crystallization nucleation of in situ fibrillar and spherical inclusions in poly (phenylene sulfide)/isotactic polypropylene blends, J Macromol Sci Part B Phys 44 761-778. 

Recent work on crystallinity measurements is reported below sulfur containing ether ketones [14], polyethylene glycol [15], polystyrene (PS) [16, 17], (PC) [18], polyphenylene alkene diyls [19, 20], isotactic polypropylene [20, 21], polyethylene [21, 22], polyimide [23], poly(2,5 bis (4-methoxyphenyl) oxycarbonyl styrene [24], polyazomethine esters [25], PET-polybutylene terephthalate blends [26], polycyclohexyl ethylene copolymers [27], polycaprolactone [28], syndiotactic polystyrene [29, 30], polyvinylidene fluoride-trifluorethylene copolymer [30], polyethers [31], isotactic methyl methacrylate [32], soy protein isolate polymers [33], polyamide 6/66 [34], polytrimethylene-2,6-naphthalate [35, 36], PE like polyesters [37], polycyclohexadiene [38], p-dioxolone, L-lactide - polyethylene glycol copolymers [39], ethylene - methacrylic acid copolymers and ionomers [40]. 

There are other examples of small amounts of copolymers inducing mechanical property enhancement in blends. Paul and his coworkers [51, 52] describe the use of ethylene blocks in a blocky ethylene propylene copolymer to compatiblize polyethylene and isotactic polypropylene. They also found in another study [53] that hydrogenated styrene-butadiene triblock copolymer enhanced the mechanical properties of polyethylene and poly(ethylene terephthalate) (Fig. 6.4). 

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