Chemicals property determination

Abstract

A method of determining or predicting a value P.sub.x of a property of a material X, which is a feed to a process or a property of a product of a process from said material or yield of said process, which method comprises measuring the absorption D.sub.i x of said material at more than one wavelength in the region 600-2600 nm, comparing the said absorptions or a derivative thereof with absorptions D.sub.i m or derivatives thereof at the same wavelength for a number of standards S in a bank for which the said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the absorption D.sub.i x (or derivative thereof) for the material and the absorption D.sub.i m (or derivative thereof) for the standards S.sub.m to obtain P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.m is chosen, and wherein said process is at least one of polymerization, an oligomerization or an organic reaction in which at least one of the reactant and a product is a functionalized compound.