Addition of additives to polymeric materials
AssigneeBASF SE
InventorFrank R. Jones
Life of this patent
Estimating the term…
Abstract
Additives are introduced into a thermoplastic melt by feeding at least one additive in an aqueous vehicle containing a dispersant to form an aqueous additive stream to a vented extruder which is extruding a thermoplastic followed by volatilizing an aqueous portion of the aqueous additive stream and removing substantially all the volatilized aqueous portion through the extruder vent to achieve a substantially homogeneous system containing the thermoplastic and at least one additive and forming a fiber from the homogeneous system by extrusion of the system through a spinneret.
Claims23
A process for introducing additives into a thermoplastic melt comprising:
- a) feeding at least one additive in an aqueous vehicle containing a dispersant to form an aqueous additive stream to a vented extruder which is extruding a thermoplastic;
- b) volatilizing the aqueous portion of the aqueous additive stream;
- c) removing substantially all the volatilized aqueous portion through the extruder vent to achieve a substantially homogeneous system containing the thermoplastic and at least one additive;
- and
- d) forming a fiber from the homogeneous system by extrusion of the system through a spinneret.
A process for introducing additives into a thermoplastic melt comprising:
- a) feeding an additive in an aqueous vehicle containing a dispersant into a twin screw extruder which is extruding a thermoplastic melt stream;
- b) mixing the thermoplastic and additive in the extruder;
- c) removing the aqueous portion from the resulting mixture while in the extruder;
- d) extruding a resulting substantially homogeneous thermoplastic and additive melt;
- and
- e) forming a fiber from the substantially homogeneous thermoplastic and additive.
A process for extruding fiber directly from a thermoplastic melt and an additive in an aqueous vehicle containing a dispersant comprising:
- a) using a twin screw extruder as the main extruder extruding molten polymer in a fiber spinning process;
- b) injecting at least one additive in an aqueous vehicle into the extruder at such a rate as to give the desired additive concentration in the fiber;
- c) removing the injected aqueous portion of the vehicle in the vent section of the extruder;
- and
- d) shaping the resulting modified molten thermoplastic polymer into a fiber.
Dependencies are inferred from the claim text.