Hollow fibres, process for their manufacture and their applications especially in the field of separations using membranes

• Main Author: PHILIPPE APTEL ET JEAN-MICHEL ESPENAN
• Format: Patent
• Language: English; French
• Published: 20.12.1985
• Edition: 4
• Subjects: APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBONFILAMENTS; CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS,THREADS, FIBRES, BRISTLES OR RIBBONS; MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OFARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES ORRIBBONS; NATURAL OR ARTIFICIAL THREADS OR FIBRES; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; SPINNING; TEXTILES; TRANSPORTING

Hollow fibres based on fibre-forming polymeric substances, characterised in that they are of asymmetric structure in the sense that they have a relatively dense layer (''skin'') H of very small thickness < 1 mu m at their outer periphery, which is connected to a so-called ''open'' structure J whose porosity increases in the direction of the inner wall, the said open structure underlying the said skin consisting of a microporous layer directly in contact with the said skin and characterised by the presence of pores of dimensions greater than 0.1 mu m and smaller than 2 mu m and of a macroporous layer exhibiting macrovoids I which have a main dimension greater than 2 mu m, the proportion of these macrovoids representing at least 10 % by volume of the wall. L'INVENTION CONCERNE DES FIBRES CREUSES A BASE DE SUBSTANCES POLYMERES FIBROGENES CARACTERISEES PAR LE FAIT QU'ELLES SONT DE STRUCTURE ASYMETRIQUE EN CE SENS QU'ELLES PRESENTENT UNE COUCHE RELATIVEMENT DENSE ("PEAU") H DE TRES FAIBLE EPAISSEUR 1 MM A LEUR PERIPHERIE EXTERNE, LAQUELLE EST LIEE A UNE STRUCTURE DITE "OUVERTE" J DONT LA POROSITE AUGMENTE LORSQU'ON SE DIRIGE VERS LA PAROI INTERNE, LADITE STRUCTURE OUVERTE SOUS-JACENTE A LADITE PEAU SE COMPOSANT D'UNE COUCHE MICROPOREUSE DIRECTEMENT AU CONTACT DE LADITE PEAU ET CARACTERISEE PAR LA PRESENCE DE PORES DE DIMENSIONS SUPERIEURES A 0,1MM ET INFERIEURES A 2MM ET D'UNE COUCHE MACROPOREUSE PRESENTANT DES MACROVIDES I AYANT UNE DIMENSION PRINCIPALE SUPERIEURE A 2MM, LA PROPORTION DE CES MACROVIDES REPRESENTANT AU MOINS 10 EN VOLUME DE LA PAROI.