Optical properties of polycarbonate/styrene-co-acrylonitrile blends: effects of molecular weight of the matrix

Abstract

In this paper, the effects of the molecular weight of a polycarbonate (PC) matrix on the phase morphology and optical properties of a PC/styrene-co-acrylonitrile (SAN) blend were investigated. A scanning electron microscope is used to analyze the phase morphology of the blends, and Mie scattering theory is used to analyze the changing laws of the optical properties of PC/SAN blends with the increasing of PC molecular weight. Results show that the average particle diameter is not strongly changed with different PC molecular weight because the values of the viscosity ratios are very close to each other. But it is obvious that the number of large particles gradually reduced while small particles (especially d<2 μm) significantly increased with the increasing of PC molecular weight. And the increase in small particles will result in an increase in backward scattering so the transmittance of PC/SAN blends decreases with the increase of PC molecular weight. However, the balance of the scattering coefficients and the number concentration of particles eventually lead to the haze of the blends being very close, despite having different PC molecular weights. Meanwhile, the photographs of scattering patterns indicate that the PC/SAN blends whose component weight ratios are fixed at 70:30 have excellent antiglare properties, despite the changes in molecular weight of the PC matrix.

In-situ fabrication of a novel anisotropic PC-matrix light-scattering materials containing spindle-shaped core-shell particles

“…Among them,where m is the relative refractive index between particle ( n 2 ) and matrix ( n 1 ), d is the diameter of the sphere, λ is the incident wavelength, I is scattering intensity(watt/m 2 ), r is the distance from the center of the sphere, I 0 is the incident light intensity (watt/m 2 ), θ 0 is the scattering angle, and are the Riccati–Bessel functions, and , are the Legendre and associated Legendre functions of cos θ , respectively 5 .…”

Light scattering materials with tunable optical properties by controlling refractive index of the dispersed phase

“…1 Traditionally, inorganic additives or organic particles like silica (SiO 2 ), 2 titanium dioxide (TiO 2 ), 3 polysiloxane, core-shell particles, 4 and ordinary polymer blends such as poly(ethylene terephthalate), 5 ethylene-vinyl acetate, 6 and poly(styrene-coacrylonitrile) (SAN), [7][8][9] are commonly incorporated into polymer matrix to prepare optical diffusers with excellent transmittance and high haze. 1 Traditionally, inorganic additives or organic particles like silica (SiO 2 ), 2 titanium dioxide (TiO 2 ), 3 polysiloxane, core-shell particles, 4 and ordinary polymer blends such as poly(ethylene terephthalate), 5 ethylene-vinyl acetate, 6 and poly(styrene-coacrylonitrile) (SAN), [7][8][9] are commonly incorporated into polymer matrix to prepare optical diffusers with excellent transmittance and high haze.…”

“…Optical diffusers are widely used in artificial lightings, illuminated sign, automotive dashboards, liquid crystal displays, and so forth, to improve the brightness uniformity on the displays. 1 Traditionally, inorganic additives or organic particles like silica (SiO 2 ), 2 titanium dioxide (TiO 2 ), 3 polysiloxane, core-shell particles, 4 and ordinary polymer blends such as poly(ethylene terephthalate), 5 ethylene-vinyl acetate, 6 and poly(styrene-coacrylonitrile) (SAN), [7][8][9] are commonly incorporated into polymer matrix to prepare optical diffusers with excellent transmittance and high haze.…”

“…2,[10][11][12][13][14] Our previous work also showed that the transmittance and haze of Polycarbonate (PC)/SAN light diffusion sheets increase simultaneously with the increase of SAN mass fraction. 9 Other than modifying particle size and additives concentration, a growing amount of attentions have been paid on tailoring the materials' refractive index to control the optical properties. [14][15][16] Generally, the modulation of the refractive index is achieved through manipulating the structures or the constituent of the hybrid materials.…”