Polymer Science Overview - American Chemical Society

5 Polymer Science Through the Fifties C. S. M A R V E L

Downloaded by PURDUE UNIV on May 28, 2016 | http://pubs.acs.org Publication Date: December 10, 1981 | doi: 10.1021/bk-1981-0175.ch005

University of Arizona, Department of Chemistry, Tucson, AZ 85721

I shall confine my remarks to the development of polymer science in America. There was considerable work before that in Europe, but that was before chemistry of polymers became sophisticated and real progress was made in the field. In about 1910 industrial work on polymers began to be carried out, although the understanding of polymers was very meager. The industrial work was done mainly on natural products such as horn and hoof and they were converted into useable materials by various means without much understanding of the real chemistry involved. Horns and hooves were the raw materials for the early polymer preparations. These materials were ground up and treated in various ways so that they could be fabricated into such items as combs to use for ladies' h a i r , and other specialty things of that sort. The next development was the use of cellulose from cotton or from wood as the raw material which was studied for making films and fibers. Work on the cellulose structure had provided information that it was a hydroxylated product, and by converting the hydroxyls to esters, the natural cellulose could be turned into a soluble material, which was spun into fibers and cast into films to make the first cellulose rayon-type material and c e l l u lose films. One o f t h e e a r l i e r m e t h o d s w a s t o t r e a t c e l l u l o s e w i t h s o d i u m hydroxide and carbon d i s u l f i d e t o obtain xanthate e s t e r s which c o u l d be d i s p e r s e d i n w a t e r and c a s t i n t o s h e e t s o r spun i n t o fibers. Subsequent t r e a t m e n t w i t h a c i d decomposed t h e x a n t h a t e s and gave r e g e n e r a t e d c e l l u l o s e , e i t h e r i n f i b e r o r f i l m f o r m . The f i b e r s w e r e c a l l e d v i s c o s e r a y o n a n d t h e f i l m s w e r e named c e l l o phane. C e l l o p h a n e i s s t i l l u s e d a s a w r a p p i n g f i l m a n d some o f i t i s s t i l l manufactured by t h e xanthate p r o c e s s . By t r e a t m e n t w i t h n i t r i c a c i d , c e l l u l o s e was c o n v e r t e d t o a t r i n i t r i e a c i d e s t e r , w h i c h c o u l d be c a s t i n t o u n i t s w h i c h were s a t i s f a c t o r y f o r making gun c o t t o n f o r a s m o k e l e s s powder f o r e i t h e r a r t i l l e r y s h e l l s o r shotgun ammunition. I t was q u i t e i n s o l u b l e b u t i t c o u l d be c o n v e r t e d t o a j e l l y - l i k e m a s s , w h i c h c o u l d be shaped i n t o a d e s i r e d form f o r ammunition u s e . Under m i l d e r c o n d i t i o n s , a lower n i t r a t e

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0097-6156/81/0175-0053$5.00/0 1981 American Chemical Society

Stahl; Polymer Science Overview ACS Symposium Series; American Chemical Society: Washington, DC, 1981.


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POLYMER SCIENCE OVERVIEW

o f c e l l u l o s e c o u l d be made w h i c h was c a l l e d p y r o x y l i n , a n d t h i s was s o l u b l e i n e t h e r a n d a c e t o n e . T h i s m a t e r i a l c o u l d a l s o be s p u n i n t o a f i l m o r a f i b e r a n d t h e f i l m was a c t u a l l y much u s e d in photographic work. B u t i t was q u i t e h a z a r d o u s b e c a u s e o f t h e high f l a m m a b i l i t y . When b l e n d e d w i t h c a m p h o r , p y r o x y l i n e g a v e c e l l u l o i d , w h i c h was u s e d f o r m a k i n g b u t t o n s , c o l l a r s , c u f f s , a n d s o f o r t h . Again, t h e f l a m e h a z a r d was g r e a t . S o l u t i o n s of p y r o x y l i n were used to make f i l m s t o c o v e r c u t s , b r u i s e s , b u r n s , e t c . b u t t h e f i r e hazard was g r e a t . L a t e r c e l l u l o s e was t r e a t e d w i t h a c e t i c a n h y d r i d e and s u l f u r i c a c i d t o g i v e a l o w e r a c e t a t e w h i c h was s o l u b l e i n a c e t o n e and w h i c h c o u l d be c a s t i n t o f i l m s o r spun i n t o f i b e r s . The f i l m s w e r e much u s e d f o r p h o t o g r a p h i c f i l m s a n d w e r e much s a f e r t h a n t h e nitrate films. A c e t a t e r a y o n was made t h i s w a y . It is s t i l l a product of the t e x t i l e i n d u s t r y . The a c e t a t e q u i c k l y t o o k t h e p l a c e o f the n i t r a t e i n f i l m s and f i b e r s . Some m i x e d e s t e r s o f a c e t i c o r b u t y r i c a c i d were prepared to g i v e a molding p l a s t i c w h i c h had c o n s i d e r a b l e u s e a t one t i m e . T r u e s y n t h e t i c p o l y m e r s came i n t o u s e when B a k e ! a n d came f r o m B e l g i u m and a p p l i e d h i s knowledge o f the f o r m a t i o n o f a m o l d a b l e p l a s t i c f r o m p h e n o l a n d f o r m a l d e h y d e t o g i v e t h e p r o d u c t named Bakélite. T h i s was a b o u t 1914. T h i s p r o d u c t , under heat and p r e s s u r e , s e t up t o a t h e r m o - s e t t i n g r e s i n a n d h a d u s e f u l p r o p e r t i e s e s p e c i a l l y a s an i n s u l a t i n g m a t e r i a l f o r e l e c t r i c a l items. I t i s s t i l l w i d e l y m a n u f a c t u r e d and used f o r such purposes and i n t h e m a k i n g o f v a r n i s h e s and f i n i s h e s o f one s o r t o r a n o t h e r . The chemical r e a c t i o n s i n v o l v e d i n the f o r m a t i o n of B a k é l i t e were not known a t t h a t t i m e , b u t t h e c o n d i t i o n s f o r m a n u f a c t u r i n g some v a r i e t i e s w e r e w e l l w o r k e d o u t s o t h a t t h e y c o u l d be p r e p a r e d on a large scale. S o o n a f t e r t h e B a k é l i t e e r a came o t h e r s y n t h e t i c p l a s t i c s . T h e g l y p t a l s made f r o m p h t h a l i c a n h y d r i d e a n d g l y c e r o l w e r e d e v e l o p e d as c o m p o s i t i o n s f o r use i n p a i n t s and v a r n i s h e s . If the r e a c t i o n was c a r r i e d o u t t o o l o n g t h e p r o d u c t became i n t r a c t i b l e . But u n d e r m i l d e r c o n d i t i o n s , o t h e r p r o d u c t s c o u l d be o b t a i n e d w h i c h c o u l d be u s e d i n m a k i n g s o l u b l e p r o d u c t s and t h e n t h e y c o u l d be s e t f u r t h e r a f t e r f o r m i n g . I t was l e a r n e d t h a t by m o d i f y i n g t h e r e a c t i o n m i x t u r e w i t h some m o n o b a s i c a c i d t o b a l a n c e t h e h y d r o x y l s and c a r b o x y l s i n t h e r e a c t i o n m i x t u r e , more s o l u b l e p r o d u c t s c o u l d be o b t a i n e d . K i e n l e o f G e n e r a l E l e c t r i c , was one o f the e a r l y developers of these products. L a t e r many o t h e r a l k y d r e s i n s f r o m o t h e r p o l y h y d r o x y l compounds and p o l y a c i d s were p r o duced f o r t e c h n i c a l u s e . A n o t h e r o f t h e e a r l y t h e r m o - s e t t i n g r e s i n s was t h e u r e a f o r m a l d e h y d e r e s i n d e v e l o p e d by A m e r i c a n C y a n a m i d . Urea and f o r m a l d e h y d e g a v e m e t h y l o l a n d d i m e t h y l o l u r e a w h i c h on h e a t i n g , f u r t h e r condensed to give the c o l o r l e s s r e s i n . The t e c h n o l o g y of t h i s p r o c e s s was w e l l w o r k e d o u t , b u t t h e c h e m i s t r y was s t i l l not completely understood. The c o l o r l e s s r e s i n h a s b e e n u s e d t o make many v a r i e t i e s o f d e c o r a t i v e m a t e r i a l s a n d some e s s e n t i a l l y u n b r e a k a b l e d i s h e s , among o t h e r u s e s .



5.

MARVEL

Polymer Science Through the Fifties

55

The n e x t p r o d u c t s d e v e l o p e d w e r e t h e t h e r m o p l a s t i c s made b y vinyl polymerization. V i n y l c h l o r i d e , and v i n y l a c e t a t e c o p o l y mers known as V i n y l i t e , was one o f t h e f i r s t p r o d u c e d by C a r b i d e and C a r b o n . I t h a d b e e n w o r k e d on i n E u r o p e a n d h a d a l s o b e e n w o r k e d on by O s t r o m y s s l e n s k i , a c h e m i s t w i t h t h e U. S . Rubber Company. The C a r b i d e c h e m i s t s r e a l i z e d a t an e a r l y d a t e t h a t to g e t a u n i f o r m c o m p o s i t i o n i t was n e c e s s a r y t o a d j u s t t h e f e e d r a t i o s o f t h e two monomers t o g e t a p r o p e r c o m b i n a t i o n i n t h e r e actor to give a constant composition to the product. The next m a j o r d e v e l o p m e n t o f a v i n y l p r o d u c t was i n t h e d e v e l o p m e n t of Lucite or P l e x i g l a s polymers, which are c l e a r , strong p l a s t i c s . The c l a r i t y o f t h e s e p l a s t i c s made t h e m v e r y u s e f u l f o r c a n o p i e s f o r f i g h t e r p i l o t s t o p r o t e c t them f r o m b u l l e t s i n b a t t l e . Their s t r e n g t h and c l a r i t y a r e two v e r y i m p o r t a n t p r o p e r t i e s w h i c h make them s t i l l most u s e f u l . Their resistance to sunlight i s very good. A l l o f t h e s e d e v e l o p m e n t s came a l o n g b e f o r e c h e m i s t s u n d e r s t o o d what polymers r e a l l y were. O r i g i n a l l y , they were b e l i e v e d t o be m a t e r i a l s h e l d t o g e t h e r i n m a s s b y some a c t i v e f o r c e s o t h e r than normal v a l e n c e f o r c e s . In a b o u t 1920 Hermann Staudinger r e a l i z e d t h a t polymers were m a c r o m o l e c u l e s h e l d t o g e t h e r by normal valence forces. He u n d e r s t o o d t h a t p o l y m e r s w e r e r e a l l y a m i x t u r e of l a r g e m o l e c u l e s o f d i f f e r e n t m o l e c u l a r w e i g h t and they had p r o p e r t i e s i m p a r t e d t o them by t h i s v e r y s e t o f c i r c u m s t a n c e s . The high v i s c o s i t i e s of these m o l e c u l e s were connected w i t h the molec u l a r w e i g h t a n d t h e r e was a f i x e d r e l a t i o n s h i p o f v i s c o s i t i e s w i t h m o l e c u l a r w e i g h t w h i c h c o u l d be m e a s u r e d t o t e l l w h a t p r o g r e s s was b e i n g made i n s y n t h e s i s . I t r e m a i n e d f o r C a r o t h e r s , who j o i n e d t h e D u P o n t o r g a n i z a t i o n i n 1 9 2 8 , t o show t h a t S t a u d i n g e r ' s v i e w t h a t p o l y m e r s were t r u l y m a c r o m o l e c u l e s was c o r r e c t and t h a t t h e y c o u l d be f o r m e d by n o r m a l c h e m i c a l r e a c t i o n s , and t h u s show t h e c h a r a c t e r i s t i c s o f p o l y m e r molecules. Staudinger's views of the natures of polymer s t r u c t u r e s w e r e s o u n d , b u t he d i d n o t r e a l l y d e m o n s t r a t e t h e m e x p e r imentally. I t r e m a i n e d f o r C a r o t h e r s t o do t h a t w i t h h i s c o n densation polymers. Carothers fashioned polymeric m a t e r i a l s such as p o l y e s t e r s and p o l y a m i d e s and o t h e r polymers by s e l f - r e a c t i n g m o l e c u l e s l i k e hydroxy a c i d s , amino a c i d s o r d i - h y d r o x y ! compounds and d i a m i n o compounds w i t h d i b a s i c a c i d s . He c l a r i f i e d t h e i d e a s of r e c u r r i n g u n i t s i n p o l y m e r s , of b i - f u n c t i o n a l m o l e c u l e s , end groups, r e a c t i v i t y r a t i o s , v i s c o s i t y molecular weight r e l a t i o n s , e t c . , s o t h a t f u r t h e r p r o g r e s s i n t h e f i e l d c o u l d be more r e a d i l y made. I n a s h o r t p e r i o d o f t i m e , a b o u t 10 y e a r s , h e d i s c o v e r e d t h a t p o l y a m i d e s such as p o l y - h e x a m e t h y l e n e a d i p a m i d e gave a s t r o n g p l a s t i c t h a t c o u l d be spun f r o m a m e l t t o g i v e an o r i e n t e d f i b e r , w h i c h was c a l l e d N y l o n . I t ' s i n t e r e s t i n g to r e c a l l that i n the extreme excitement of t h i s d i s c o v e r y , the group working a t the Experimental S t a t i o n at DuPont d i d n o t r e a l i z e t h a t p o l y - h e x a m e t h y l e n e a d i p a m i d e was a



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v a l u a b l e p o l y m e r f o r f i b e r f o r m a t i o n , a n d no p a t e n t was f i l e d . The w o r k d i d g o on on p o l y e s t e r s w h i c h w e r e more s i m p l e t o w o r k w i t h , and i t was w h i l e w o r k i n g w i t h t h o s e t h a t J u l i a n H i l l disc o v e r e d t h e y c o u l d be drawn i n t o f i b e r s . He n o t e d t h a t b y d r a w i n g a s t i r r i n g r o d o u t o f a m o l t e n p o l y e s t e r , he o b t a i n e d a t h r e a d w h i c h , on s t r e t c h i n g , l o o k e d s i l k y . E x a m i n i n g t h e t h r e a d he f o u n d t h e p o l y m e r m o l e c u l e s h a d b e e n o r i e n t e d l o n g i t u d i n a l l y a n d made them much more s t a b l e f i b e r s i n t h i s w a y . The p o l y e s t e r s were t o o low m e l t i n g t o make t e x t i l e f i b e r s . H o w e v e r , when he a p p l i e d t h i s c o l d drawing t o polyamides they gave good s i l k y t h r e a d s w h i c h were u s e f u l a s t e x t i l e f i b e r s a n d he was a b l e t o make m a t e r i a l s f r o m p o l y a m i d e s which had p r o p e r t i e s t h a t were s a t i s f a c t o r y f o r t e x t i l e use. I t was t h e c o l d d r a w i n g p a t e n t s t h a t gave D u P o n t i t s monopoly f o r the s t a r t of s y n t h e t i c f i b e r s . O t h e r t e x t i l e f i b e r s s u c h a s p o l y e t h y l e n e t e r e p h t h a l a t e came i n t o p r o d u c t i o n f i r s t i n England and then i n A m e r i c a . The E n g l i s h d i s c o v e r e d the f i b e r and the Americans d i s c o v e r e d the f i l m . When i t was drawn b i - a x i a l l y , p o l y e t h y l e n e t e r e p h t h a l a t e gave a v e r y good f i l m w h i c h has had w i d e u s e . C a r o t h e r s ' s w o r k was m a i n l y i n t h e f i e l d o f c o n d e n s a t i o n polymers. He d i d m a k e o n e s i g n i f i c a n t c o n t r i b u t i o n t o a d d i t i o n polymers. C a l c o t t a t J a c k s o n L a b o r a t o r y had n o t e d F a t h e r N i e u w l a n d ' s w o r k on t h e d i m e r i z a t i o n a n d t r i m e r i z a t i o n o f a c e t y l ene and f e l t t h e s e monomers s h o u l d be u s e f u l i n m a k i n g a s y n t h e t i c rubber. He a c q u i r e d t h e p a t e n t r i g h t s f r o m F a t h e r N i e u w l a n d for t h i s d i s c o v e r y a n d t h e n b e g a n w o r k i n g on t h e s e p r o d u c t s t o s e e i f he s h o u l d c o n v e r t t h e m i n t o r u b b e r . A f t e r some y e a r s o f w o r k , h e w e n t t o C a r o t h e r s f o r h e l p and a s k e d C a r o t h e r s i f he w o u l d l i k e t o have t h e s e two monomers t o s t u d y . Carothers thought they would be i n t e r e s t i n g . One o f h i s e a r l y a c t s w a s t o a s s i g n t o A r n o l d C o l l i n s t h e t a s k o f p u r i f y i n g some o f t h e s e m o n o m e r s , a n d c a r r y i n g out the d i s t i l l a t i o n of the crude p o l y m e r i z a t i o n product from acetylene, C o l l i n s noticed a small intermediate f r a c t i o n of l i q u i d which b o i l e d between m o n o v i n y l a c e t y l e n e and d i v i n y l a c e t y l e n e . It was l a t e i n t h e d a y and he s e t t h i s s m a l l s a m p l e a s i d e t o t a k e care of l a t e r . When h e r e t u r n e d o n t h e n e x t w o r k i n g d a y , h e f o u n d t h a t the i n t e r m e d i a t e f r a c t i o n had s o l i d i f i e d and had rubbery p r o perties. In f a c t , i t w o u l d b o u n c e on t h e t a b l e . He e x a m i n e d i t and f o u n d t h a t i t r e a l l y was t h e h y d r o c h l o r i c a c i d a d d i t i o n p r o d u c t o f m o n o v i n y l a c e t y l e n e , w h i c h had been formed a l o n g w i t h t h e dimer and t r i m e r of a c e t y l e n e . When h e s u b s e q u e n t l y f o u n d o u t how t o p r o d u c e i t , h e p a t e n t e d i t a n d t h e f i r s t u s e f u l s y n t h e t i c r u b b e r , N e o p r e n e , came f r o m i t s p o l y m e r i z a t i o n . Neoprene i s s t i l l the o i l - r e s i s t a n t strong rubber of choice i n i n d u s t r y . W h i l e C a r o t h e r s and h i s group were s t u d y i n g c o n d e n s a t i o n p o l y m e r s , o t h e r i n d u s t r i a l companies were s t u d y i n g v i n y l polymeri z a t i o n and g e t t i n g b a s i c u n d e r s t a n d i n g o f t h a t p r o c e s s . The d i s covery that vinyl polymerization developed in three d i s t i n c t s t a g e s — i n i t i a t i o n , p r o p a g a t i o n , a n d t e r m i n a t i o n — d i d much t o g i v e an u n d e r s t a n d i n g o f t h e p r o c e s s . I n i t i a t i o n c o u l d be by


5.

MARVEL


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r a d i c a l f o r m a t i o n o r b y a n i o n i c p r o c e s s , d e p e n d i n g on t h e t y p e o f monomer. P r o p a g a t i o n was a r a p i d s t e p w h e r e t h e a c t i v a t e d monomer attached to the growing polymer c h a i n . T e r m i n a t i o n c o u l d be by chain t r a n s f e r , disproportionation, or coupling. The v a r i o u s m e t h o d s o f t e r m i n a t i o n d e p e n d e d t o some e x t e n t on t h e monomers used i n the study of the p o l y m e r i z a t i o n . The e a r l y w o r k was l a r g e l y on v i n y l c h l o r i d e - v i n y l a c e t a t e copolymers. O s t r o m y s s l e n s k i a t U. S . R u b b e r Company d i d a l o t o f w o r k o n t h e v i n y l i t e s ; t h e Rohm a n d H a a s g r o u p a n d D u P o n t w e r e most a c t i v e i n t h e methyl m e t h a c r y l a t e polymers ( L u c i t e and Plexiglas). The d i s c o v e r y o f p l a s t i c i z a t i o n o f p o l y v i n y l c h l o r i d e by W a l d o Semon o f G o o d r i c h u s i n g t r i c r e s y l p h o s p h a t e a n d d i o c t y l p h t h a l a t e was a v e r y i m p o r t a n t s t e p i n t h e d e v e l o p m e n t o f u s e f u l p r o d u c t s f r o m p o l y v i n y l c h l o r i d e s o t h a t t h i s p o l y m e r became one of the leading v i n y l products that i s produced. The work o f Mayo a n d W a l l i n g a t U. S . R u b b e r on r e a c t i v i t y r a t i o s o f monomers a i d e d g r e a t l y i n making copolymers o f d e f i n i t e c o m p o s i t i o n and u n i f o r m i t y . P r i c e a n d A l f r e y a l s o c o n t r i b u t e d much i n t h i s f i e l d . B e f o r e t h e m e c h a n i s m o f v i n y l p o l y m e r i z a t i o n was u n d e r s t o o d , t h e q u e s t i o n o f t h e s t r u c t u r e o f v i n y l p o l y m e r s was o f c o n s i d e r able interest. S t a u d i n g e r had w r i t t e n t h e s e polymers as h a v i n g a h e a d - t o - t a i l a r r a n g e m e n t o f r e c u r r i n g u n i t s , b u t he h a d n o t r e a l l y f u r n i s h e d evidence of the s t r u c t u r e . As C a r o t h e r s once s a i d , S t a u d i n g e r had a s s i g n e d t h e s t r u c t u r e by p r o n o u n c e m e n t . He w a s a s u s u a l c o r r e c t , and c h e m i c a l e v i d e n c e was d e v e l o p e d t o e s t a b l i s h such s t r u c t u r e s . F o r e x a m p l e , when m o n o v i n y l m e t h y l k e t o n e p o l y m e r i z e d , i t c o u l d p r o d u c e by h e a d - t o - h e a d , t a i l - t o - t a i l r e a c t i o n a 1,4-diketone. By h e a d - t o - t a i l p o l y m e r i z a t i o n i t w o u l d g i v e a 1,5-diketone. These two t y p e s have d i f f e r e n t r e a c t i o n s . The s t u d y o f t h e p o l y m e r p r o p e r showed t h a t t h e p o l y m e r was a 1 , 5 diketone. In t h e c a s e o f p o l y v i n y l c h l o r i d e , a h e a d - t o - h e a d , t a i l - t o - t a i l p o l y m e r i z a t i o n would l e a d to a 1 , 2 - d i h a l i d e compound, and a h e a d - t o - t a i l p o l y m e r i z a t i o n would l e a d t o a 1 , 3 - d i h a l i d e . I t was t h e l a t t e r t h a t was p r o d u c e d as shown by t h e f a c t t h a t o n l y a b o u t 86% o f t h e c h l o r i n e was r e m o v e d b y t r e a t i n g t h e p o l y m e r w i t h copper. L a t e r i t was shown t h a t t h i s t r e a t m e n t p r o d u c e d c y c l o propane u n i t s i n the c h a i n so t h a t the q u e s t i o n of h e a d - t o - t a i l s t r u c t u r e was d e f i n i t e l y e s t a b l i s h e d . A few p o l y m e r s do have s t r u c t u r e s c o n t a i n i n g both h e a d - t o - t a i l and h e a d - t o - h e a d , t a i l - t o tail structures. When v i n y l f l o u r i d e i s p o l y m e r i z e d , a c e r t a i n p e r c e n t a g e o f t h e f l o u r i n e atoms a r e f o u n d on a d j a c e n t c a r b o n a t o m s . When p o l y v i n y l a l c o h o l made by h y d r o l y z i n g p o l y v i n y l a c e t a t e was t r e a t e d w i t h p e r i o d i c a c i d by F l o r y , he f o u n d t h a t t h e m o l e c u l a r w e i g h t was g r e a t l y r e d u c e d , i n d i c a t i n g t h a t t h e r e w e r e 1 , 2 - g l y c o l units in the c h a i n . But most o f the polymers were r e g u l a r h e a d - t o - t a i l polymers. Vinyl government Firestone,

p o l y m e r i z a t i o n was a d v a n c e d a g r e a t d e a l d u r i n g t h e rubber program. The r e s e a r c h g r o u p s o f U. S . Rubber, G o o d y e a r , and G o o d r i c h , t o g e t h e r w i t h u n i v e r s i t y groups



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from Massachusetts I n s t i t u t e of Technology, C o r n e l l , Case, C h i c a g o , I l l i n o i s , and M i n n e s o t a , and the i n d u s t r i a l groups of E s s o , B e l l T e l e p h o n e , and DuPont, c o l l a b o r a t e d i n a v e r y e f f e c t i v e program to produce a u s e f u l r u b b e r . When t h e w a r c u t o f f t h e s u p p l y from the Far E a s t , w i t h i n a y e a r t h e s e r e s e a r c h groups had made a p r o d u c t t h a t w a s s a t i s f a c t o r y f o r p a s s e n g e r c a r s . The g o v e r n m e n t s e t up a r u b b e r c z a r i n W a s h i n g t o n t o s e e t h a t a l l p r i o r i t i e s f o r s u p p l i e s needed were p r o v i d e d to t h i s r e s e a r c h group. I n d u s t r i a l companies b u i l t p l a n t s f o r making rubber before t h e e x a c t p r o c e s s f o r i t s m a n u f a c t u r e was s e t t l e d . B u t , they were v e r y e f f e c t i v e a n d p r o d u c e d r u b b e r a t a b o u t 150% o f t h e r a t e d capacity. When t h e u r g e n c y w a s o v e r , t h e g o v e r n m e n t s o l d t h e p l a n t s back t o i n d u s t r y and i t i s s a i d t h a t the whole o p e r a t i o n was p r o f i t a b l e . With minor m o d i f i c a t i o n s that rubber i s s t i l l used f o r passenger cars. I t i s n o t s u i t a b l e f o r l a r g e t r u c k s and bomber t i r e s because of the excess of heat b u i l d - u p i n o p e r a t i o n . Before t h e end o f t h e r u b b e r p r o g r a m , two o f t h e c o m p a n i e s , F i r e s t o n e and G o o d r i c h , had d e v e l o p e d p r o c e s s e s t h a t p r o d u c e d r u b b e r e s s e n t i a l l y like natural rubber. F i r e s t o n e used a l i t h i u m c a t a l y s t f o r the p o l y m e r i z a t i o n , and G o o d r i c h used a m o d i f i e d Z i e g l e r c a t a l y s t . These m a t e r i a l s were manufactured f o r a w h i l e u n t i l the o i l p r i c e s became t o o p r o h i b i t i v e and t h e n a t u r a l r u b b e r was a g a i n u s e d f o r heavy-duty t i r e s . I n d u s t r y d e v e l o p e d p o l y m e r s from most o f t h e c h e a p e r raw m a t e r i a l s d u r i n g t h i s p e r i o d , and p r o d u c t i o n of t h e s e p r o d u c t s rose to the b i l l i o n s of pounds. S p e c i a l t y polymers were a l s o p r o duced such as epoxy r e s i n s , f l u r o c a r b o n p o l y m e r s , and t h i o k o l r u b b e r s , w h i c h h a v e made a c o m e b a c k f o r u s e i n d e v e l o p i n g f u e l for spaceships. P o l y s t y r e n e developed remarkably a f t e r pure s t y r è n e became a v a i l a b l e t h r o u g h t h e r u b b e r p r o g r a m . ABS r e s i n s ( b u t a d i e n e - s t y r e n e - a c r y l o n i t r i l e t e r p o l y m e r s ) , came i n t o u s e f o r making a v e r y s t r o n g f i l m f o r luggage and a u t o m o b i l e s e a t s f o r rugged wear. I t i s o u r o n l y t e r p o l y m e r w h i c h i s made i n l a r g e quantities in industry. I n c o n c l u s i o n , I w a n t t o p a y my r e s p e c t s t o P r o f e s s o r H e r m a n M a r k , whom we a r e h o n o r i n g t o d a y . He h a s b e e n a v e r y i m p o r t a n t f a c t o r i n the development of polymer chemistry i n America. He came t o B r o o k l y n a n d o n e o f h i s f i r s t a c t s was t o a r r a n g e a s e m i n a r on S a t u r d a y m o r n i n g s on p o l y m e r c h e m i s t r y , w h i c h h a d t h e attendance of the l o c a l polymer chemists i n the a r e a , both from i n d u s t r y and the u n i v e r s i t i e s . T h i s was an i m p o r t a n t s t i m u l u s t o a l l , t o b e b r o u g h t u p t o d a t e o n w h a t w a s new a n d t o g e t t o g e t h e r a n d t a l k o v e r t h e new p r o d u c t s . He s t a r t e d t h e f i r s t P o l y m e r I n s t i t u t e o f A m e r i c a i n B r o o k l y n a n d t r a i n e d many o f o u r a c t i v e polymer chemists. He f o u n d e d t h e J o u r n a l o f P o l y m e r S c i e n c e , w i t h i t s Chemistry E d i t i o n , Physics E d i t i o n , Polymer L e t t e r s ; the J o u r n a l o f A p p l i e d Polymer S c i e n c e ; and t h e r e g u l a r r e p o r t s o f i m p o r t a n t polymer symposiums b e i n g h e l d throughout the w o r l d .


5.

MARVEL


59

He w a s l a r g e l y r e s p o n s i b l e f o r t h e f o u n d i n g o f t h e Polymer D i v i s i o n of the American Chemical S o c i e t y . He w a s a c t i v e a s a c o n s u l t a n t i n i n d u s t r y and u n i v e r s i t y g r o u p s , thus s t i m u l a t i n g t h e c h e m i s t s and k e e p i n g them up t o d a t e . His c o n t a c t s were i n t e r n a t i o n a l and i n t h i s way he h e l p e d t o e x c h a n g e information in the f i e l d around the w o r l d . H i s a c t i v i t i e s have been a g r e a t s t i m u l a n t t o t h e p r o g r e s s o f polymer c h e m i s t r y i n A m e r i c a and throughout the w o r l d . A t the end o f 1950, A m e r i c a had r e a l l y a r r i v e d a t Age and p r o g r e s s has c o n t i n u e d , as w i l l be s e e n i n t h e w i l l be g i v e n l a t e r i n t h i s S y m p o s i u m .

the Polymer talks that


RECEIVED February 5 , 1 9 8 1 .


Polymer Science Overview - American Chemical Society

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