Natta / Danusso Stereoregular Polymers and Stereospecific Polymerizations

The Contributions of Giulio Natta and His School to Polymer Chemistry
1. Auflage 2013
ISBN: 978-1-4832-2385-8
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 442 Seiten

Stereoregular Polymers and Stereospecific Polymerizations, Volume 2 covers the reactions and physico-chemical properties of various polymers. This volume is divided into 88 chapters, and starts with the survey of the molecular structure, stereospecific polymerization, and reaction kinetics of styrene. Considerable chapters are devoted to copolymerization reaction, crystallinity of block copolymers, and molecular weight and isotactic behavior determination. Other chapters examine other polymer properties, such as elastomeric activity, enthalpy, entropy, and resonance of energy. This book also considers the polymerization of vinyl monomers, conjugated diolefins, and butadienes. These topics are followed by presentations of various metallic complexes as polymerization reaction catalysts. The remaining chapters describe the proposed nomenclature of polymer products obtained from other stereospecific polymerization reactions. This book will prove useful to polymer chemists.

Autoren/Hrsg.

Natta, Giulio

Danusso, Ferdinando

Leseproben

85

PRESENT SITUATION AND PROSPECTS OF THE ITALIAN CHEMICAL INDUSTRY — HIGH POLYMER DEVELOPMENTS

GIULIO NATTA

(June 1958) [, 114 (1958)]

Publisher Summary

This chapter explains how the Italian chemical industry started and progressed in the last decades, what is the present stage of evolution and especially, and the trends of its future developments. The Italian territory is rich neither in coal fields —only very low-grade lignites are available at very high cost—nor in petroleum and in important metallic ores, with the exception of bauxite and iron pyrites. The Italian chemical industry started using air, water, salt, and pyrites as raw materials; plants were initially located where power was locally available or where it was possible to use seasonal surplus of hydroelectric power. The availability of electric energy not only made it possible to start certain electrolytic productions—such as those of chlorine, soda, and aluminum—but also of synthetic ammonia from electrolytic hydrogen and of methanol from synthesis gas. The latter was produced in the continuous low-temperature coal gasification plants, which were the first in the world that used oxygen, obtained as a by-product of electrolytic hydrogen production or of nitrogen production by air fractionation.

The present and the future situation of the Italian chemical industry is the topic I am going to deal with especially from the point of view of its historical, economic and evolutionary bases. I shall neglect all statistical data concerning the various chemical productions, since they are reported in many other publications.

In this short paper I shall try to give an idea of how the Italian chemical industry started and progressed in the last decades, what is the present stage of evolution and especially the trends of its future developments.

I hope that this outline will be of interest: I will try to demonstrate how a spirit of enterprise, hard work and confidence has overcome the initial difficulties.

THE PRESENT SITUATION AND ITS ORIGIN

The Italian territory is neither rich in coal-fields (only very low grade lignites are available at very high cost) nor in petroleum and in important metallic ores, with the exception of bauxite and iron pyrites.

It is well known that the primary factors promoting the progress of the chemical industry are the availability of raw materials and the general technological level. In Italy, raw materials are very few. We can say that the Italian chemical industry started using air, water, salt and pyrites as raw materials; plants were initially located where power was locally available or where it was possible to use seasonal surplus of hydroelectric power.

The availability of electric energy not only made it possible to start certain electrolytic productions, like those of chlorine, soda, aluminium, but also of synthetic ammonia (in 1924) from electrolytic hydrogen, and of methanol (in 1928) from synthesis gas. The latter was produced in the continuous low temperature coal gasification plants, which were the first in the world that used oxygen, obtained as a by-product of electrolytic hydrogen production or of nitrogen production by air fractionation. The local availabilities of power were taken up in more economically rewarding uses, as the civil consumption was growing, the country being in a development phase. Therefore, power became ever less available to the chemical industry.

In a densely populated country, like Italy, where tillable areas are limited, though extended to the most impervious and least fertile mountainous districts, it was obvious to focus research on the field of phosphatic fertilizers (needed in soils depleted by thousands of years of cultivation) and of nitrogen fertilizers. The latter field promoted the growth in the 1925’s of the great chemical industry in Italy.

From this starting platform, the Italian chemical industry, in the period between the two World Wars, developed toward more complex productions, like dyestuffs and pharmaceuticals. At the same time, rayon was manufactured on a large scale; its production was favoured by the existing textile industry of natural fibres. Thus Italy became one of the leading exporters of this cellulose fiber.

In that period, Italy also made great strides in the production of ammonia, calcium carbide, inorganic and organic acids and calcium cyanamide.

Although the Italian chemical industry started later than in other European countries, it developed some original concepts and techniques, which, in some instances, contributed to the development of the world chemical industry. Such contribution is considerably greater than would have been predicted by the sole consideration of the limited Italian productions.

As an example, we quote the high pressure synthesis processes (ammonia, methanol) developed in Italy and the manufacturing units connected with them, which led to the construction of several plants in Europe, America and Asia.

In the years immediately before World War II the Italian chemical industry had tackled new advanced problems. Hydrocarbon hydrogenation plants were then built in Bari and Leghorn, where some very heavy Albanian crude oils were used. The main purpose of these industries was the production of fuels (thus they were not strictly petrochemical plants), but there was already a trend to utilize certain by-products to yield chemicals.

In the field of synthetic rubber, a plant was built in Ferrara in 1938 for the production of butadiene from alcohol and Buna S. This plant comprised a unit, the first in the world, that allowed the separation by extractive distillation of substances, like butadiene and butylene, having about the same boiling point. A plant for the manufacture of Buna S starting from calcium carbide was being built in Terni, when the war broke out and the work was interrupted.

The development of the Italian chemical industry was halted also in the first post-war period, when all efforts were directed to rebuild the productive structure of the whole country. Thus in 1954–46 the chemical production dropped to figures much below those of 1938.

In the last 10 years, the Italian people with great energy and capacity for work, have not only rebuilt their towns and industries, but have also increased production and welfare to a level exceeding considerably that reached before the war, as indicated by the monetary values shown in Table 1.

TABLE 1

ITALIAN CHEMICAL PRODUCTION

1938

414

1948

414

1958

1160

In the meantime, a deep change in the old conceptions on the raw materials suitable for the chemical industry took place in Italy, probably before that in other European countries.

Before the war, the European chemical industry was mostly based on coal, whereas petroleum was neglected. However, two new and important factors arose: the availability of new raw materials and the development of olefin chemistry.

After 1947, gas oil fields were found and exploited in Northern Italy. Table 2 shows the production from 1948 to 1957.

TABLE 2

ITALIAN PRODUCTION OF NATURAL GAS

1948

113

4,210

1949

240

8,950

1950

490

18,300

1951

930

34,700

1952

1,380

51,500

1953

2,200

82,000

1954

2,870

107,000

1955

3,490

130,000

1956

4,300

160,000

1957

4,820

180,000

In addition, the recent increase in oil production in the Middle East, the ever more efficient and economical transportation means and, last but not least, the geographical position of Italy, have allowed the development of a petroleum industry that now reaches an approximate capacity of 30 million tons of crude per year. This has opened up new possibilities for the chemical industry.

The technique of obtaining chemical products from gaseous or liquid hydrocarbons was mostly developed in the U. S. A. during the war, while it was almost unknown in Europe where, instead of using the petroleum hydrocarbons as raw material for chemical syntheses, years of work were spent to attain the opposite goal, namely synthetic gasoline. That conception and the rationalization of chemical engineering are rightly considered a major contribution by the U.S.A. to the development of the chemical industry.

After the war, chemical production from hydrocarbons was developed in Italy. Italian people again showed considerable energy and spirit of enterprise and further contributed to the progress of chemistry. Two main trends were followed:...