RAPID COOLING EFFECT IN POLYPROPYLENE MELT SPINNING-INFLUENCE OF STRESS

Optimal Control of Melt Spinning Processes

An optimal control problem for a mathematical model of a melt spinning process is considered. Newtonian and non–Newtonian models are used to describe the rheology of the polymeric material, the fiber is made of. The extrusion velocity of the polymer at the spinneret as well as the velocity and temperature of the quench air serve as control variables. A constrained optimization problem is derive...

The influence of branching efficiency on the rheology and morphology of melt state long chain branched polypropylene/polybutene-1 blends

In this study, the compatibility of the blends of polypropylene (PP) and polybutene-1(PB-1) homopolymer before and after long chain branching process were studied. The blends were prepared and long-chain branched directly via reactive extrusion process in presence of free radical initiator and trimethylolpropane tri methacrylate (TMPTMA) poly functional monomer. The optimum percentage of TMPTMA...

Thermal Stability of P-Type BiSbTe Alloys Prepared by Melt Spinning and Rapid Sintering

P-type BiSbTe alloys have been widely implemented in waste heat recovery from low-grade heat sources below 600 K, which may involve assorted environments and conditions, such as long-term service, high-temperature exposure (generally 473-573 K) and mechanical forces. It is important to evaluate the service performance of these materials in order to prevent possible failures in advance and exten...

Effect of Melt Spinning Variables on the Structural Changes of Recycled and Bottle Grade Filament Yarn PET

Evaluation of Simultaneous Effect of Melt Filtration and Cooling Rate on Tensile Properties of A356 Cast Alloy

The combined influence of both melt filtration and cooling rate on the microstructure features and mechanical properties of A356 cast alloy was studied. A step casting model with five different thicknesses was used to obtain different cooling rates. The effect of melt filtration was studied by using of 10 and 20 ppi ceramic foam filters in the runner. Results showed that secondary dendrite arm ...