Ziegler-Natta catalyst resins

Ziegler-Natta catalyst. A comparison of properties of resins and their extruded film samples are given in Table 5. 

Polypropylene grades manufactured using Ziegler-Natta catalysts are predominandy isotactic, with a comparatively broad molecular weight distribution (Afw/Mn 3.5). Ziegler-Natta catalyzed polypropylene comprises the majority of commodity grade resins. 

Polyethylene polymers history of, 17 701-702 simulations of, 16 747 Polyethylene products, Ziegler-Natta catalysts for, 26 540-543 Polyethylene resins, 17 700-703 applications for, 17 703 Polyethylenes, classification of, 17 701t. 

Polyolefin industry, catalysts in, 26 503 Polyolefin (PO) resins, 17 699-700 technologies and uses for, 17 707-708 Polyolefin products, Ziegler-Natta catalysts for, 26 533-544 Polyolefins, 10 518... 

PS PSF PSU PTFE PU PUR PVA PVAL PVB PVC PVCA PVDA PVDC PVDF PVF PVOH SAN SB SBC SBR SMA SMC TA TDI TEFE TPA UF ULDPE UP UR VLDPE ZNC Polystyrene Polysulfone (also PSU) Polysulfone (also PSF) Polytetrafluoroethylene Polyurethane Polyurethane Poly(vinyl acetate) Poly(vinyl alcohol) poly(vinyl butyrate) Poly(vinyl chloride) Poly(vinyl chloride-acetate) Poly(vinylidene acetate) Poly(vinylidene chloride) Poly(vinylidene fluoride) Poly(vinyl fluoride) Poly(vinyl alcohol) Styrene-acrylonitrile copolymer Styrene-butadiene copolymer Styrene block copolymer Styrene butadiene rubber Styrene-maleic anhydride (also SMC) Styrene-maleic anhydride (also SMA) Terephthalic acid (also TPA) Toluene diisocyanate Ethylene-tetrafluoroethylene copolymer Terephthalic acid (also TA) Urea formaldehyde Ultralow-density polyethylene Unsaturated polyester resin Urethane Very low-density polyethylene Ziegler-Natta catalyst... 

Commercial polystyrene, one of the most representative general-purpose resins, is an amorphous atactic polymer with no melting point (softening temperature ca 100 °C, glass transition temperature ca 70-100 °C). Since the discovery of Ziegler-Natta catalysts, many efforts to produce stereoregular polystyrenes have been made. 

The Ziegler-Natta catalyst trimethylammonium o-methyl-1-(2-hydroxy Icy do hexyl)-carborane zirconium chloride has been prepared and affixed to a Merrifield resin. When used as a polymerization catalyst for vinyl chloride, t-butyl acrylate, styrene, or ethylene, oligomers with molecular weights <6000 daltons were obtained. 

If a copolymer such as VLDPE or LLDPE is the target resin, satisfactory comonomer incorporation must be achieved. This is manifested by the amount of comonomer incorporated (evidenced by density) and the distribution of comonomer in the polymer (evidenced by composition distribution). In general, supported chromium oxide catalysts incorporate comonomer more easily than Ziegler-Natta catalysts. 

Since the discovery of Ziegler-Natta catalyst, isotactic polypropylene has been widely used as a commodity material due to its low cost and excellent physical properties. As the modulus of the resin is closely related to isotacticity, an understanding in polymerization mechanism is important in the chemistry of propylene polymerization as well as in the industry. 

Sukhadia, A. M., Trade-offs in blown film LLDPE type resins from chromium, metallocene and ziegler-natta catalysts. Journal of Plastic Film Sheeting 2000,16, (1), 54-70. 

Figure 2.3 Generic CCD of a LLDPE resin made with a heterogeneous Ziegler-Natta catalyst. Chains with more SCBs have lower crystallization temperatures than chains with fewer SCBs.

Looking again at Figure 2.7, it will be remembered that resins such as LLDPE made with heterogeneous Ziegler-Natta catalysts and tandem reactors have a rather complex relation between MWD and average comonomer composition. Because this relation has such an important impact on the mechanical properties of polyolefins, an FTIR detector is often added to the GPC (GPC/RI-FTIR) to measure comonomer fraction as a function of molecular weight. 

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