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Ionic Chain-Reaction and Complex Coordination Polymerization 173

available to the general public. Management was getting glowing reports about the potential for
these new materials. On the basis of these assessments, $50 million was committed for the construc-
tion of a large-scale PE plant at Adams Terminal.
Several things were in operation that is not immediately apparent. First, the great investment of
money and time needed to bring a product into the marketplace. At that time $50 million was a lot
of money, on the order of half a billion dollars today. Second, up to that time, technicians with little
training were used in much of the chemical industry. The “educated” chemists were kept behind
the research benches discovering “new” things. Most of the PhD chemists were in fact in universi-
ties rather than in industry. (Today, only about 15% of the professional chemists are teaching, the
remainder are in industry and government.) Because of the sensitivity of the catalyst system used to
produce the new polymers, substantially greater training had to be given to workers who dealt with
the production of these new polymers. Third, this was a venture into a new arena by Phillips, up to
now solely a gasoline-producing company. Finally, while not initially apparent, the catalysts used to
produce these new polymers were part of a new group of catalysts being investigated internationally
by many companies that allowed the production of so-called stereoregular polymers.
As noted previously, PP and other alpha olefins, can reside in three main stereoregular forms dif-

ferentiated from one another because of the precise geometry of the methyl group as the polymer is
formed. When the methyl groups reside on the same side as one looks down a barrow of the chain,
as below, it is called isotactic-PP or simply iPP.

H C H H C H H C H H C H H C H H C H H C H
3
3
3
3
3
3
3
R
(5.53)
R
The methyl group can also exist in alternate positions as shown below. This form is called syn-
diotactic-PP or simply sPP.
H C H H CH 3 H C H H CH 3 H C H H CH 3 H C H
3
3
3
3
R
(5.54)
R
The third structure consists of mixtures of the syndiotactic and isotactic structures favoring
neither structure. This mixture of structures is called the atactic form (aPP) the “a” meaning hav-
ing nothing to do with. Space-filling modes of all these three different tactic forms are given in

Figure 5.5.
Each particular tactic form has its own physical properties. Table 5.4 contains representative val-
ues for iPP. The syndiotactic and isotactic forms are referred to as stereoregular forms and allow the
chains to better fi t together giving a material that is crystalline while the aPP is amorphous. Being
crystalline causes the polymer to be stronger, denser, less porous to small molecules like water and
oxygen, and to have a higher melting temperature. The old PP is of the atactic form and the form
synthesized by Hogan and Banks is iPP. Only recently, using soluble stereoregulating systems has
sPP become commercially available.
Other groups were working on developing these stereoregulating catalysts. In fact, more research
dollars and effort was spent during the 1950s developing these stereoregulating catalysts than that
spent on cancer research during that time. The competition was fi erce and monetary stakes high. I
was present at one of the initial presentations of the results from a number of different groups. Each
group believed their catalyst system gave the best results and each believed that the product they
obtained was the same product that other companies obtained. There were several times during the
presentations where the groups would yell at one another and physically wrench the microphone

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