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OK THE STRUCTURE OF RUBBER’ R.HOUWINK The Rubber Foundation, Delft, Netherlands Received June 8, 1941 I. INTRODUCTIOK
I t \vi11 not be necessary to explain to readers of this journal that rubber is made up of long-chain molecules in “knauel”2 form. However, in recent times a few more perfections have come t o light., which \vi11 be examined more closely in this paper. II. THE
‘‘XKXUEL”
STRUCTURE
After Staudinger’s m-ell-known conception of the rubber molecule in the form of rigid rods had gradually been pushed into the background ( 6 ; cf. also I), the assumption, especially of Kuhn (13) and of Guth and Mark ( 5 ; cf. also the more recent publications mentioned in references 2, 3, 4, 11, and 15), of the 1
Communication Xo. 27 from The Rubber Foundation, Delft, Netherlands.
* The German word “I
