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Transparency of polymer blends
Author(s) -
Maruhashi Yoshitsugu,
Iida Setsuko
Publication year - 2001
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.10895
Subject(s) - materials science , polyethylene terephthalate , polymer , polymer blend , composite material , haze , anisotropy , refractive index , transparency (behavior) , light scattering , scattering , polymer science , chemical engineering , optics , optoelectronics , copolymer , organic chemistry , chemistry , physics , political science , law , engineering
Polymer blending is useful for improving physical properties. Blends of transparent polymers are generally hazy. However, transparency is required in many products such as packages (especially PET bottles). The miscible blends, PET (polyethylene terephthalate)/PBT (polybuthylene terephthalate), maintain transparency in almost all cases regardless of the blending ratio, whereas the immiscible blends, PET/MxNYLON (MXD6 nylon, i.e. polymethaxylirene adipamide) and PET/PMAI (polymethacril imide, i.e. N‐methyl dimethyl glutarimide) become hazy as the blending ratio increases. The reason for this haze is the number and size of the dispersed particles. Differences in the refractive indices of various polymers also have a large influence on haze. Stretching makes even the transparent blends hazy in the case of PET/MxNYLON. One reason for this phenomenon is that stretching increases the size of the dispersed particles in the sheet plane. A second reason is that the difference in the anisotropic refractive indices of the matrix and the dispersed phase is increased by stretching. These effects are very consistent with light scattering theory.