| 摘要 |
An extrusion die for extruding biodegradable material, the extrusion die including: a mandrel; an outer member positioned near the mandrel; an extrusion orifice between the mandrel and the outer member; a member in communication with at least one defining member of the extrusion orifice, wherein the member is capable of producing relative movement between the outer member and the mandrel, wherein the relative movement has a component transverse to an extrusion direction of biodegradable material through the extrusion orifice; a flow control device which controls flow of biodegradable material through the extrusion die; and a positioning device which positions the outer member and the mandrel relative to each other. An improved process for the extrusion of biodegradable material wherein the extrusion includes flowing the biodegradable material in a flow direction through an orifice, the improvement including: moving the biodegradable material in a direction having a component transverse to the flow direction during extrusion; controlling the flow rate of biodegradable material through the extrusion die during extrusion, wherein the controlling includes adjusting the head pressure of the biodegradable material in the extrusion die and adjusting at least one cross-sectional area of a biodegradable material flow path within the extrusion die; and modifying the orifice geometry.
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