X‐ray diffraction and ultrasonics velocity measurements of esterified maleic and fumaric resins

The esterified maleic and fumaric resins have been studied by X‐ray diffraction. Their diffraction halos have been subjected to a Fourier analysis for the first time and the physical parameters like particle size, percentage crystallanity and electrondensity fluctuations along the length of the polymer molecule have been evaluate out by standard methods. The results indicate that the two resins are isomeric in nature. This conclusion is further supported by a measurement of the variation in ultrasonic velocity with concentration in xylene solutions of these resins.