Technology Study of Polypropylene Hollow Fiber Membranes-Like Artificial Lung Made by the Melt-Spinning and Cold-Stretching Method

Abstract

Artificial lung also called as oxygenator which performs a function of exchanging O2 and removing CO2 from blood. Due to its good performance at the exchange area, oxygenation, etc, hollow fiber membranes have become the main research direction of artificial lung. Polypropylene (pp) hollow fiber membranes made by the melt-spinning and cold-stretching methods (MSCS) in this study. Through the research on the membrane manufacture process and technology optimization to prepare suitable membrane for artificially lung. The performance of membrane was affected by the melt-draw ratio and spinning temperature, annealing temperature, and the proportional relations of cold stretch with hot stretch. The results of the study show that improve melt-draw ratio, select the appropriate annealing conditions and the reasonable ratio of hot stretch with cold stretch can effectively increase the air flux of pp hollow fiber membrane.

Porous Fiber Processing and Manufacturing for Energy Storage Applications

“…Traditionally, the method of melt-spinning and cold-stretching (MSCS) consists of multiple steps to produce hollow porous fibers as reported in [76]. Three typical steps were used to prepare polyethylene (PE) [77][78][79], polypropylene (PP) [80][81][82], and polyvinylidene fluoride (PVDF) [83] porous hollow fiber membranes. In the first step, melt-spinning was conducted.…”

Polypropylene Hollow Fiber Membrane by Dissolution-Inducing Pore Methods

“…In the MS process, researchers studied the structural evolution of hollow membranes at different annealing temperatures [ 19 ], strength fields [ 20 ], and the effect of stretching ratio on pore size distribution [ 21 ]. Liu found that the extrusion rate and stretching temperature are the main factors for the gas flux of hollow fiber membrane as an artificial lung [ 22 ]. However, the limitations of TIPS and MS include pore diameters larger than 50 nm [ 23 , 24 , 25 , 26 ], which cannot meet the requirements of ECMO [ 27 , 28 ] for leading to plasma penetration [ 27 , 29 , 30 , 31 , 32 ], and this will pose a threat of infection to surrounding medical staff and cause dangerous biological pollution to the environment [ 33 ].…”

Interconnected, microporous hollow fibers for tissue engineering: Commercially relevant, industry standard scale‐up manufacturing

“…Micropores allow a diffusion path for nutrients into the scaffold and removal of cellular waste products. Micropores can be created after the spinning process via cold stretching, thermally induced phase separation (TIPS), or by introducing a secondary sacrificial component into the base polymer . Subsequent removal of the sacrificial component leaves a microporous network throughout the fiber wall generated by the primary polymer.…”

“…Several methodologies to form micropores are described in published literature and patents. These include the addition of soluble additives, thermally induced phase separation, and melt spinning cold stretching …”

“…More recently, Liu et al investigated the effect of draw ratio and annealing time on the air flux of microporous hollow PP membranes fabricated via MSCS. A nearly linear increase in air flux was observed with increasing draw ratio from 1000 to 2700 . Shen et al reported similar results during the formation of porous PE membranes .…”