# US 2013/0158179 A1 · Injection Molding of Polyarylene Sulfide Compositions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0158179 A1 - Document ID: US20130158179A1 - Status: Published application - Kind: A1 - Application number: 13/709,175 - Filed: 2012-12-10 - Published: 2013-06-20 - Earliest claimed: 2011-12-16 - Assignees: Ticona LLC - Inventors: Ke Feng; Peter Radden; Michael Schafer - Web page: https://patentgrep.com/patent/US20130158179A1 ## CPC - C08K 3/38: Boron-containing compounds - B29C 45/0001: {characterised by the choice of material} - B29C 45/73: of the mould {(B29C45/2642 and B29C45/2737 take precedence)} - F04D 29/026: {especially adapted for liquid pumps} - F04D 29/2222: {Construction and assembly (F04D29/2211 takes precedence)} - F04D 29/42: for radial or helico-centrifugal pumps - F04D 29/426: {especially adapted for liquid pumps} - B29K 2081/04: {Polysulfides, e.g. PPS, i.e. polyphenylene sulfide or derivatives thereof} - B29K 2105/0005: {containing compounding ingredients (releasing, lubricating or separating agents B29C33/56, fibers B29K2105/08, B29K2105/12; fillers B29K2105/16, recycled material B29K2105/26)} - F05D 2230/20: essentially without removing material - F05D 2300/43: Synthetic polymers, e.g. plastics; Rubber - F05D 2300/605: Crystalline - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - 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) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - 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 - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A method for injection molding a thermoplastic composition that contains a polyarylene sulfide and a boron-containing nucleating agent is provided. By selectively controlling certain aspects of the polyarylene sulfide and nucleating agent, as well as the particular manner in which they are combined, the crystallization properties of the resulting thermoplastic composition can be significantly improved. This allows the “cooling time” during a molding cycle to be substantially reduced while still achieving the same degree of crystallization. The cooling time can be represented by the “normalized cooling ratio”, which is determined by dividing the total cooling time by the average thickness of the molded part. ## Claims ### Claim 1 A method for injection molding a thermoplastic composition, the method comprising: injecting a thermoplastic composition into a mold cavity, wherein the thermoplastic composition comprises a polyarylene sulfide and a boron-containing nucleating agent; subjecting the thermoplastic composition to a cooling cycle to form a molded part having a certain average thickness, wherein the cooling cycle has a normalized cooling ratio of from about 0.2 to about 8 seconds per millimeter, as determined by dividing the total time of the cooling cycle by the thickness of the molded part; and ejecting the molded part from the mold cavity. ### Claim 2 (depends on 1) The method of claim 1, wherein the normalized cooling ratio is from about 1 to about 5 seconds per millimeter. ### Claim 3 (depends on 1) The method of claim 1, wherein the total time of the cooling cycle is from about 5 to about 40 seconds, and wherein the average thickness of the molded part is from about 0.5 to about 15 millimeters. ### Claim 4 (depends on 1) The method of claim 1, wherein the mold temperature is from about 50° C. to about 120° C. ### Claim 5 (depends on 1) The method of claim 1, wherein the mold temperature is from about 70° C. to about 90° C. ### Claim 6 (depends on 1) The method of claim 1, wherein the water is used as a cooling medium during the cooling cycle. ### Claim 7 (depends on 1) The method of claim 1, wherein polyarylene sulfides constitute from about 30 wt. % to about 95 wt. % of the composition and boron-containing nucleating agents constitute from about 0.01 wt. % to about 6 wt. % of the composition. ### Claim 8 (depends on 1) The method of claim 1, wherein the boron-containing nucleating agent includes boron nitride. ### Claim 9 (depends on 1) The method of claim 1, wherein the composition further comprises an impact modifier, mineral filler, fibrous filler, organosilane coupling agent, lubricant, disulfide, or a combination thereof. ### Claim 10 (depends on 1) The method of claim 1, wherein the composition has a crystallization potential of about 52% or more, as determined by differential scanning calorimetry in accordance with ISO 10350. ### Claim 11 (depends on 1) The method of claim 1, wherein the molded part has a tensile strength of from about 100 to about 500 MPa, as determined in accordance with ISO Test No. 527 at 23° C. ### Claim 12 (depends on 1) The method of claim 1, wherein the molded part has a tensile strength of from about 120 to about 400 MPa, as determined in accordance with ISO Test No. 527 at 23° C. ### Claim 13 (depends on 1) An injection molded part formed according to the method of claim 1. ### Claim 14 (depends on 13) A liquid pump comprising the injection molded part of claim 13. ### Claim 15 (depends on 14) The liquid pump of claim 14, wherein the pump is a direct lift pump, positive displacement pump, rotodynamic pump, or gravity pump. ### Claim 16 (depends on 14) The liquid pump of claim 14, wherein the pump is a centrifugal pump for circulating a coolant through an automotive engine. ### Claim 17 (depends on 13) An electronic component comprising the injection molded part of claim 13. ### Claim 18 (depends on 17) The electronic component of claim 17, wherein the component is a cellular telephone, laptop computer, small portable computer, wrist-watch device, pendant device, headphone or earpiece device, media player with wireless communication capabilities, handheld computer, remote controller, global positioning system device, handheld gaming device, battery cover, speaker, camera module, or integrated circuit. ### Claim 19 A centrifugal pump for circulating a coolant through an automotive engine, wherein the pump comprises: a pump impeller that is configured to flow the coolant radially outward into a volute chamber; and a housing that encloses the pump impeller and volute chamber, wherein at least a portion of the pump impeller, the housing, or both comprise a molded part formed from a thermoplastic composition that comprises a polyarylene sulfide and boron-containing nucleating agent.