# US 2010/0244304 A1 · Stents fabricated from a sheet with increased strength, modulus and fracture toughness > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0244304 A1 - Document ID: US20100244304A1 - Status: Published application - Kind: A1 - Application number: 12/415,841 - Filed: 2009-03-31 - Published: 2010-09-30 - Earliest claimed: 2009-03-31 - Inventors: Yunbing Wang - Web page: https://patentgrep.com/patent/US20100244304A1 ## CPC - B29D 23/001: {Pipes; Pipe joints (pleated hoses B29D23/18)} - A61F 2/92: Stents in the form of a rolled-up sheet expanding after insertion into the vessel {, e.g. with a spiral shape in cross-section} - A61F 2210/0004: bioabsorbable - A61F 2210/0076: multilayered, e.g. laminated structures - A61F 2250/0031: made from both resorbable and non-resorbable prosthetic parts, e.g. adjacent parts - B23K 2103/42: {Plastics other than composite materials} - B23K 2103/50: {Inorganic materials other than metals or composite materials} - B29C 53/40: for articles of definite length, i.e. discrete articles - B29C 55/04: uniaxial, e.g. oblique - B29C 2035/1658: {using gas} - B29K 2105/24: crosslinked or vulcanised - B29K 2995/006: Bio-degradable, e.g. bioabsorbable, bioresorbable or bioerodible - B29L 2023/007: {Medical tubes other than catheters (catheters B29L2031/7542)} - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract Methods of fabricating a polymeric stent from a polymer sheet with improved strength, modulus and fracture toughness are disclosed. The methods include stretching the polymer sheet along one or more axesto increase the strength, fracture toughness, and modulus of the polymer along the axis of stretching. The methods further include forming a tubular stent from the stretched sheet. The stent can include a slide-and-lock mechanism that permits the stent to move from a collapsed diameter to an expanded diameter and inhibiting radial recoil from the expanded diameter. ## Claims ### Claim 1 A method of making a stent comprising: stretching polymer sheet along an axis, wherein the stretching increases the strength, fracture toughness, and modulus of the polymer; and forming a tubular stent from the stretched sheet, the stent comprising a slide-and-lock mechanism, the slide and lock mechanism permitting the stent to move from a collapsed diameter to an expanded diameter and inhibiting radial recoil from the expanded diameter. ### Claim 2 (depends on 1) The method of claim 1, wherein the polymer sheet is made from a biodegradable polyester selected from the group consisting of PLLA and PLGA. ### Claim 3 (depends on 1) The method of claim 1, wherein the polymer sheet comprises or is made from a tyrosine-derived polycarbonate. ### Claim 4 (depends on 1) The method of claim 1, wherein the slide and lock mechanism comprises circumferentially adjacent modules, the modules including longitudinally adjacent slide-and-lock radial elements which permit one-way sliding of the radial elements from the collapsed diameter to the expanded diameter and inhibit radial recoil from the expanded diameter. ### Claim 5 (depends on 1) The method of claim 1, wherein a cylindrical axis of the stent is parallel, perpendicular, or at an angle between parallel and perpendicular to the axis of stretching. ### Claim 6 (depends on 1) The method of claim 1, further comprising stretching the sheet along a second axis of stretching to provide biaxial orientation to the sheet, wherein a cylindrical axis of the tube is parallel, perpendicular, or at an angle between parallel and perpendicular to the second axis of stretching. ### Claim 7 (depends on 6) The method of claim 6, wherein the axis of stretching is perpendicular to the cylindrical axis and the second axis of stretching is parallel to the cylindrical axis. ### Claim 8 (depends on 1) The method of claim 1, wherein the sheet consists essentially of a bioabsorbable polymer. ### Claim 9 (depends on 1) The method of claim 1, wherein the slide and lock mechanism is formed by laser cutting the stretched sheet. ### Claim 10 (depends on 1) The method of claim 1, wherein the stretching is performed at a temperature greater than or equal to a Tg of the polymer and less than a Tm of the polymer. ### Claim 11 (depends on 1) The method of claim 1, wherein the polymer is semicrystalline or amorphous with a Tg at least 10° C. above Tbody. ### Claim 12 (depends on 11) The method of claim 11, further comprising heating the polymer sheet uniformly or substantially uniformly to a temperature at least 5° C. above the Tg of the polymer and quenching the stretched sheet to a temperature below the Tg after the stretching, wherein the reduction in temperature inhibits or prevents relaxation of polymer chain orientation induced by the stretching. ### Claim 13 (depends on 1) The method of claim 1, wherein the polymer sheet is crosslinked prior to the stretching, wherein the crosslinks inhibit or prevent relaxation of the polymer chain orientation induced by the stretching, the crosslink degree being less than 5%. ### Claim 14 (depends on 1) The method of claim 1, further comprising inducing crosslinking of the polymer sheet during or after the stretching, wherein the crosslinking inhibits or prevents relaxation of polymer chain orientation induced by the stretching. ### Claim 15 (depends on 13) The method of claim 13, wherein the polymer is semicrystalline or amorphous and has a Tg greater than Tbody. ### Claim 16 (depends on 13) The method of claim 13, wherein a crosslink degree of the stretched sheet is less than 5%. ### Claim 17 (depends on 1) The method of claim 1, wherein the polymer sheet comprises nanoparticles dispersed in the polymer. ### Claim 18 (depends on 17) The method of claim 17, wherein the nanoparticles are selected from the group consisting of nanofibers and nanotubes. ### Claim 19 (depends on 1) The method of claim 1, wherein the polymer sheet comprises quantum dots dispersed in the polymer. ### Claim 20 A method of making a stent comprising: heating a polymer sheet to facilitate stretching of the sheet; stretching polymer sheet along an axis, wherein the stretching increases the strength, fracture toughness, and modulus of the polymer; actively cooling the deformed sheet to below a target temperature to stabilize the sheet at or close to a stretched state; and fabricating a stent from the deformed sheet after the cooling. ### Claim 21 (depends on 20) The method of claim 20, wherein the stent is fabricated by forming a tubular stent from the stretched sheet, the stent comprising a slide-and-lock mechanism, the slide and lock mechanism permitting the stent to move from a collapsed diameter to an expanded diameter and inhibiting radial recoil from the expanded diameter.