Ziegler second generation

The result of the early work led to development of second-generation Ziegler catalysts (23-29). These are discussed in the next section and include (i) nonsupported trivalent titanium compounds, (ii) products of treating magnesium compounds with titanium compounds, and (iii)... 

Karl Ziegler and Erhard Holzkamp liom Kaiser Wilhehn Institute. Starting in the mid-1960s a series of patents was issued for the second generation of Z-N catalyst It was later found that addition of Mg compound tenfold increased the catalyst activity... 

The majority of the research summarized in this chapter will pertain to second-generation, magnesium-containing Ziegler catalysts due to their importance to the polyethylene industry today. However, a brief summary of first generation catalysts will be included due to the historical importance of these early ethylene polymerization catalysts from an academic and industrial perspective (see Appendix 2.1 for review references on first generation Ziegler catalysts). 

Second Generation Ziegler Catalyst for the Manufacture of Polyethylene... 

The activity of these second generation Ziegler catalysts is 10-100 times more active on a titanium basis than the first-generation Ziegler catalysts, which created significant growth opportxmities in the polyethylene industry. 

Table 2.3 Titanium-based activity of various second generation Ziegler catalysts.

Therefore, suitable supports for second generation Ziegler-Natta catalyst systems must meet similar requirements in order to perform satisfactorily. 

Polyethylene manufactured with a single-site catalyst possesses several advantages relative to a similar material produced with a titanium/magne-sium-containing, second-generation Ziegler catalyst. These include ... 

Second generation Ziegler-Natta catalysts of high activity also employ particle-form technology. Therefore, the particle size, the particle size distribution and the porosity of supported second generation Ziegler-Natta catalysts needed to be controlled over a certain range. Such requirements... 

TABLE 8.3. Second Generation Ziegler-Natta Catalyst (1970). 

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