6 Conclusions
The slurry polymerization process as first described by Ziegler et al. [1–4] is still
operated in the same way today. However, there have been breakthrough inventions
in the last 60 years that have improved this process considerably. This process is
now running with super-active catalysts. The reactor volume has now reached
around 200 m
3 . There is a detailed understanding of all relevant processes on the
microscale, mesoscale, and macroscale levels. Therefore, the process can be
well controlled to be operated safely without shutdowns over long production
times and to achieve excellent quality consistency for the full product range. The
cascaded process, especially the advanced cascade process, allows the production
of polyethylenes with an outstanding combination of properties for all fields
of application. With this technology, products in the high molecular mass range
for technical applications have now reached combinations of properties so far not
known. These products for pipes and large containers can be regarded as polymer
alloys, with a solid state structure of the hard crystalline phase interconnected
across the amorphous softer phase via tie molecules anchored in the crystalline
phase. The polymerization process allows the design of the composition of these
in-situ blends to achieve the best combinations of properties. Furthermore, the
cascaded process is very flexible in product development.
Today, the slurry polymerization process is being run all over the world with
great success. The current installed capacity for the described process is around
6 million tons per year, which represents approximately one sixth of the worldwide
PE-HD production. Other processes for PE-HD production are the Phillips process,
operated with chromium-based catalysts, and other slurry processes also operated
with Ziegler-type catalyst systems [60].
Acknowledgements This article summarizes the development over many years. I want to express
my thanks to all colleagues who contributed to this development. I have also to thank DI Elke
Damm for her very appreciated advice and help in writing this article.
References
1. Ziegler K, Holzkamp E, Breil H, Martin H (1955) Angew Chem 67:426
2. Ziegler K (1964) Angew Chem 76:545
3. Ziegler K, Breil H, Holzkamp E, Martin H (1953) Patent DE 973,626 [Chem Abstr 54:14794
(1960)]
4. Martin H (1995) In: Fink G, Mu ¨lhaupt R, Brintzinger HH (eds) Ziegler catalysts. Springer,
Berlin, pp 15–34
5. Grams E, Gaube E (1955) Angew Chem 67:548
6. Schulz G, Mehnert K (1955) Kunststoffe 45:410, 589
7. Neumann IA, Bockhoff FJ (1955) Plastics 32:117
8. Richard K (1955) Kunststoffe 45:10
9. Kneip W (1955) Chem Ind 7:297
10. Sommer S, Wagener S, Ebner H (1959) Kunststoffe 49:500
The Slurry Polymerization Process with Super-Active Ziegler-Type Catalyst. . .
77
The slurry polymerization process as first described by Ziegler et al. [1–4] is still
operated in the same way today. However, there have been breakthrough inventions
in the last 60 years that have improved this process considerably. This process is
now running with super-active catalysts. The reactor volume has now reached
around 200 m
3 . There is a detailed understanding of all relevant processes on the
microscale, mesoscale, and macroscale levels. Therefore, the process can be
well controlled to be operated safely without shutdowns over long production
times and to achieve excellent quality consistency for the full product range. The
cascaded process, especially the advanced cascade process, allows the production
of polyethylenes with an outstanding combination of properties for all fields
of application. With this technology, products in the high molecular mass range
for technical applications have now reached combinations of properties so far not
known. These products for pipes and large containers can be regarded as polymer
alloys, with a solid state structure of the hard crystalline phase interconnected
across the amorphous softer phase via tie molecules anchored in the crystalline
phase. The polymerization process allows the design of the composition of these
in-situ blends to achieve the best combinations of properties. Furthermore, the
cascaded process is very flexible in product development.
Today, the slurry polymerization process is being run all over the world with
great success. The current installed capacity for the described process is around
6 million tons per year, which represents approximately one sixth of the worldwide
PE-HD production. Other processes for PE-HD production are the Phillips process,
operated with chromium-based catalysts, and other slurry processes also operated
with Ziegler-type catalyst systems [60].
Acknowledgements This article summarizes the development over many years. I want to express
my thanks to all colleagues who contributed to this development. I have also to thank DI Elke
Damm for her very appreciated advice and help in writing this article.
References
1. Ziegler K, Holzkamp E, Breil H, Martin H (1955) Angew Chem 67:426
2. Ziegler K (1964) Angew Chem 76:545
3. Ziegler K, Breil H, Holzkamp E, Martin H (1953) Patent DE 973,626 [Chem Abstr 54:14794
(1960)]
4. Martin H (1995) In: Fink G, Mu ¨lhaupt R, Brintzinger HH (eds) Ziegler catalysts. Springer,
Berlin, pp 15–34
5. Grams E, Gaube E (1955) Angew Chem 67:548
6. Schulz G, Mehnert K (1955) Kunststoffe 45:410, 589
7. Neumann IA, Bockhoff FJ (1955) Plastics 32:117
8. Richard K (1955) Kunststoffe 45:10
9. Kneip W (1955) Chem Ind 7:297
10. Sommer S, Wagener S, Ebner H (1959) Kunststoffe 49:500
The Slurry Polymerization Process with Super-Active Ziegler-Type Catalyst. . .
77