TUBE/MANDREL ASSEMBLIES
The disclosure relates to assemblies of thin-walled tubes and mandrels for use in thin wall catheter liners. For example, an assembly is provided that includes a thin-walled PTFE tube comprising walls with a thickness of less than 0.004 inches, positioned over a filled mandrel comprising PTFE with one or more fillers incorporated therein. The disclosure further provides, independently, thin-walled tubes and filled mandrels, as well as methods of making and using such components.
1 - 22 . (canceled)
23 . A tube having an inner surface, an outer surface, and an inner lumen, the tube comprising ultra-high molecular weight polyethylene (UHMWPE) with a wall thickness less than 0.0040 inches, wherein the inner surface is patterned.
24 . The tube of claim 23 , consisting essentially of UHMWPE.
25 . The tube of claim 23 , wherein the inner surface is patterned with indentations.
26 . The tube of claim 25 , wherein the indentations are substantially spherical in shape.
27 . The tube of claim 25 , wherein the indentations are irregular in shape.
28 . The tube of claim 25 , wherein the indentations are substantially homogeneous on the inner surface.
29 . The tube of claim 25 , wherein the indentations are randomly dispersed on the inner surface.
30 . The tube of claim 23 , wherein the inner surface has a minimum average surface roughness (Ra) of 8 μ-inch.
31 . The tube of claim 23 , wherein the inner surface has a minimum LMS surface roughness (Rm) of 25 μ-inch.
32 . The tube of claim 23 , wherein the coefficient of friction (COF) is below 0.07.
33 . A method of preparing a tube, comprising:
providing a preform comprising ultra-high molecular weight polyethylene (UHMWPE) and a lubricant;
extruding the preform into a tubular form;
drawing down the tubular form over a filled mandrel to give a tube with a wall thickness less than 0.0040 inches, wherein the inner surface is patterned; and
removing the tube from the filled mandrel.
34 . The method of claim 33 , wherein the tube consists essentially of UHMWPE.
35 . The method of claim 33 , wherein the filled mandrel comprises poly(tetrafluoethylene) (PTFE) with one or more fillers dispersed therein.
36 . The method of claim 35 , wherein the one or more fillers comprise microparticles.
37 . The method of claim 36 , wherein the microparticles are selected from the group consisting of glass beads, glass bubbles, clay, silica, silicates, metal oxides, calcium carbonate, metal hydroxides, and combinations thereof.
38 . The method of claim 36 , wherein the microparticles comprise a single type of microparticle.
39 . The method of claim 36 , wherein the microparticles comprise two or more different types of microparticles.
40 . The method of claim 36 , wherein the microparticles are substantially spherical in shape.
41 . The method of claim 36 , wherein the microparticles are irregular in shape.
42 . The method of claim 36 , wherein the microparticles are incorporated substantially homogeneously throughout the filled mandrel.
43 . The method of claim 36 , wherein the microparticles are randomly dispersed and give a random microstructure on a surface of the filled mandrel.
44 . The method of claim 33 , wherein the filled mandrel comprises 0.1% to 10% by weight of the filler.