|XUE, CHAO-HUA - University Of California|
|WANG, DONG - University Of California|
|XIANG, BEI - University Of California|
|SUNG, GANG - University Of California|
Submitted to: Journal Polymer Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/20/2011
Publication Date: 4/7/2011
Citation: Xue, C., Wang, D., Xiang, B., Chiou, B., Sung, G. 2011. Morphological development of polypropylene in immiscible blends with cellulose acetate butyrate. Journal Polymer Research. 18(6):1947-1953.
Interpretive Summary: Formation and morphology of non-homogeneous or immiscible polymer blends have been investigated because new, improved properties often result from the blends. Due to phase separation, the dispersed phases may take on many different forms in the blends depending on the inherent polymer properties and the processing conditions. Size and shape of the dispersed particles affect the properties of the final product. The nanofiber production process is highly productive, is reproducible, environmentally friendly or "green" and results in versatile thermoplastics. The viscosity ratio of polymer blends is an important factor in determining the particle size of the polypropylenes in blends with cellulose acetate butyrate. The particle size of the dispersed polypropylene was smaller when the viscosity ratio of polypropylene/cellulose acetate butyrate was low, and the smallest particles were obtained when the viscosity ratio 1:1. Thus, varying the composition ratio will control the diameter of polypropylene spheres. This work provides guidance to optimizating thermoplastic nanofiber fabrication and provides more understanding of thermoplastic nanofiber formation.
Technical Abstract: Isotactic polypropylenes (iPP) with different melt flow indexes were melt blended with cellulose acetate butyrate (CAB) and then prepared into microspheres or nanofibers following a novel process of producing well dispersed CAB/iPP immiscible blends and subsequent removal of the CAB matrix. The morphologies of iPP microspheres were investigated by a scanning electron microscopy, and the dimensions of iPP microspheres were evaluated. The melt viscosities of iPP, CAB, and CAB/iPP blends were measured by using a capillary rheometer. The influences of the viscosity, viscosity ratio, and composition ratio of iPP/CAB on the morphology formation of iPP in CAB matrix were studied.