Online Analysis And Study Of Phase Structure Of Polyethylene/Nylon1010 System During Blending Process

Various HDPE/PA1010 blends and HDPE/PA1010/HDPE-g-MAH blends were prepared through mechanical blending under three kinds of temprature (200℃, 214℃ and 230℃) and three kinds of rotating speed (32rpm, 48rpm and 64rpm). Phase structure and morphology evolution during the whole blending process was studied by the online Small-Angle Laser Scattering(SALS) system and online sampling. According to Debye-Bueche theory some parameters describing the phase structure, such as correlation distance ac, average chord lengths L, integral invariant Q, fractals dimension Df and so on, were calculated. The morphology of online sampled blends were observed with the help of Scanning Electron Microscope(SEM). Some parameters, such as average particle diameter d, particle diameter distribution width σ, mass center distance D and fractals dimension DfN were also calculated from SEM photos. The results of SALS and SEM are identical, which indicate that the SALS online analysis method may be suitable for the study of the polymer blends morphology during the blending process.The results showed that the blending effect became worse as dispersed phase content increased. The blending effect when HDPE was dispersed phase was worse than that when PA1010 was dispersed phase. The size of dispersed particles decreased mainly during the initial blending period and became stable in the later. The phase morphology development of HDPE/PA1010 blends accords with the development mode brought forward by Elemans: dispersed phase comes into being strip-like structure at first and nubs separate later, at last the strip-like structure disappears and comes into being spherical particles. With the increase of blending temperature, the particle size of dispersed phase first decreased and then increased, and the phase inversion region moved toward PA-lower composition. With the increase of rotating speed, the blending effect were improved initially and then declined. The addition of HDPE-g-MAH improved the blending effect greatly, deducting the acuity of phase interface, decreasing particle size and making the particle distribution more even.