STRUCTURAL FACTORS IN POLYMERIZATION 49 



face properties of matrix substances and more exact control over the structure 

 of active materials. Such control may be derived in part from experimental 

 modification of already-formed molecules but may benefit Irom the use of selected 

 synthetic products with matrix acti\ity. The possibilities for Iruittul application 

 of synthetic organic polymers as 'tailor-made' matrix substances are virtually 

 without limit. Investigations intended as an initial effort in this direction have 

 been carried out and even in an early stage of development have expanded lur- 

 ther the scope of the entire matrix study (26). Using Dowex-50, a sulfonated 

 polystyrene, with the usual reactants, it was first observed that peroxidation pro- 

 ceeded rapidly without peroxidase, providing a matrix satisfying in its structure 

 the additional requirement of substrate activation. Further experimentation 

 showed that Dowex was also selective, polymerizing isoeugenol far faster than 

 eugenol. Several reaction products were obtained, but attention was focused upon 

 one of these, a comparatively soluble substance of molecular weight ca. 520, which 

 yielded on analysis C, 66.8%; H 6.7% (compare with ethoxylated celery trimer, 

 M.W. ca. 667, C 67.1%, H 6.4% ). Analysis of the Dowex system utilized a 

 controlled sulfonic acid block with /^-toluidine and indicated operation of a mul- 

 tiple-site mechanism; that is, that products released from the matrix already 

 possess a degree of polymerization of 2 or more. This concept has been implicit 

 throughout the consideration of natural matrix substances, but is here established 

 experimentally. The exact manner in which the matrix influences polymerization 

 remains unknown, but it was suggested by Ridgeway that if it is assumed that 

 the individual monomers adsorbed on the matrix surface are arranged approxi- 

 mately as they would be in the finished polymer, the entropy decrease associated 

 with polymer formation will be small relative to the entropy decrease associated 

 with adsorption, hence to the over-all entropy change for the reaction. It is not 

 the object of the present discussion of matrix substances and polymer formation 

 to develop a theoretical physical-chemical treatment. Nevertheless it is clear from 

 the foregoing consideration of Dowex activity that a method of experimental 

 and theoretical attack upon the detailed mechanism of matrix action is available. 

 Although methodology in science is often associated with experimental detail, 

 it possesses a broader aspect as well. Thus it was pointed out initially that the 

 development of the matrix concept involved an investigation of lignification. 

 Elucidation of the mechanism whereby eugenol underwent transformation into 

 lignin depended upon development of a model system which could, in effect, 

 reduce to its essentials the active fraction of the cell. The matrix concept was thus 

 a natural development of the effort directetl toward evaluating the role of the 

 cell wall. During the foregoing discussion of lignin synthesis by model systems, 

 the pattern of development and refinement may have been obscured by considera- 

 tion of results as they pertain to lignin and lignification per se. The essentials ot 

 the various experimental systems have therefore been abstracted and summarized 



