Industrial Research 



105 



E. I. du Pont de Nemours & Company 



Nylon. — In the 12 j'cars of operation of fundamental 

 research, substantial contributions have been made to 

 the company's progress, as indicated by the following 

 description of the nylon development: 



The first study undertaken in fundamental research 

 program was directed to a better understanding of how 

 and why certain molecules unite to form giant molecules, 

 such as those found in rubber, cellulose, and resins. 

 Chemists have long been vitally interested in giant 

 molecules, or "superpolymers," and in learning every- 

 thmg possible about the mechanism of polymerization. 



Out of the study of polymerization begun in 1928, 

 fundamental information of much importance was devel- 

 oped and was made public in the form of scientific 

 papers. It was demonstrated, for example, that cer- 

 tain small molecules could be made to unite in such a 

 way as to form giant molecules of great length, known 

 as linear superpolymers. 



However, after this fundamental research had been 

 un ler way for about 2 years, it was noted that the 

 molten polymer could be drawn out in the form of a 

 long fiber, somewhat like that of silk, and that, even 

 after the fiber was cold, it could be further drawn to 

 several times its original length. 



Wliile this original fiber was not very strong or elastic 

 and was softened by hot water, it, nevertheless, sug- 

 gested the possibility that some related type of super- 

 polymer might give fibers which would possess the char- 

 acteristics desired for use in textiles. Further research 

 was accordingly directed to the synthesis of a super- 

 polymer from which strong, elastic, and water-resistant 

 fibers would be drawn or spmi. 



Practical research directed to the synthesis of a 

 superpolymer from which fibers could be drawn suitable 

 for textile purposes did not bear immediate fruit. 

 Numerous superpolymers were synthesized. Some of 

 the resulting fibers were deficient in strength and elas- 

 ticity, while, others, although sufficiently strong and 

 elastic, softened at quite low temperatures, or were 

 sensitive to water. They did not possess the properties 

 required of a textile fiber. 



Finally a superpolymer of a different type was pre- 

 pared, a polyamide, from which fibers spun by hand 

 were found to possess such characteristics as to warrant 

 extraordinary efforts to bring the development to com- 

 mercial success. Much work was yet to be done, 

 however, between that day when the first polyamide 

 fiber was extruded through an improvised spinneret 

 made from a hypodermic needle, and the announce- 



FiGURE 21. — Ultracentrifuge for Determination of Molecular Weights of Colloidal Materials Such as Proteins, Cellulose and Rubber 

 Experimental Station of E. I. du Pont de Nemours and Company, Wilmington, Delaware 



