System for delivering ultrapure water (UPW)

Abstract

The present invention relates to a system made of poly (aryl ether ketone) polymers for delivering ultrapure water and components thereof.

Description

Citation of relevant applications

[0001] This application claims priority to U.S. Provisional Application No. 63 / 584736, filed September 22, 2023, and European Patent Application No. 23201973.7, filed October 5, 2023, the entire contents of each of these applications are incorporated herein by reference for all purposes. Technical Field

[0002] This invention relates to the delivery of ultrapure water (UPW). Background Technology

[0003] Ultrapure water (UPW) is used in many steps of semiconductor manufacturing. During manufacturing, water is used to wash and rinse semiconductor components. Water is also used for cleaning and etching operations, generating vapor for silicon surface oxidation, preparing photomasks, and depositing light-emitting materials. As semiconductor integration further advances, even higher quality water is required.

[0004] Other high-tech applications requiring UPW include the development and manufacture of solid-state devices, thin-film devices, communication lasers, light-emitting diodes, photodetectors, printed circuits, storage devices, vacuum tube devices, or electrolysis devices.

[0005] During manufacturing, up-weighted waste (UPW) as defined in ASTM D5127-07 is required to prevent product contamination, as contamination can lead to unacceptably low yields of electronic devices. Therefore, UPW needs to exhibit very low levels of inorganic cations and anions, organic contaminants, and / or biological contaminants.

[0006] The preparation of UPW involves the removal of ionic, organic, and biological contaminants, as well as particulate matter. UPW typically exhibits a resistivity of 18.1 MΩ·cm or higher at 25°C and a maximum total organic carbon (TOC) level of 10.0 µg / L. Bacterial contaminants can also be limited to 10.0 CFU / ml (CFU: colony-forming units).

[0007] Polyvinylidene fluoride (PVDF) is widely used in the manufacture of piping systems (including pipes, connectors, and other parts) for transporting ultrapure water (UPW) used in the semiconductor industry.

[0008] JPH04367781A discloses an ultrapure water delivery pipeline system comprising a terminal ultrafiltration unit or a terminal reverse osmosis membrane unit, wherein the pipeline material used after the ultrafiltration or reverse osmosis unit is made of a thermoplastic polymer containing a hydrotalcite compound and / or hydrotalcite. PEEK is mentioned among the thermoplastic polymers.

[0009] With the development of smaller chips, the purity levels required by UPW (Upgraded Polymer Wrapper) have rendered PVDF unsuitable for the entire delivery system, especially due to the leaching of organic impurities and fluoride ions in areas using higher temperatures (80°C–120°C). Indeed, the general trend today is towards producing electronic circuits with increasingly smaller linewidths. Currently, some electronics manufacturers offer commercially available chips with linewidths of approximately 400 nm. However, research projects have reported linewidths as low as 10 or even 5 nm.

[0010] Polyetheretherketone (PEEK) is described as particularly well suited as a substitute for PVDF when delivering UPW at higher temperatures (typically 80°C–120°C) because PEEK exhibits a lower leaching level compared to PVDF.

[0011] However, due to the high melting temperature of PEEK (340°C-345°C), its processing requires very high temperatures (above 360°C). Moreover, the difficulty in melting PEEK negatively impacts its feeding into the extruder and the entire extrusion process.

[0012] The use of PEEK polymers in the manufacture of pipes for use in UPW processes is known in the art, for example from US4784772 (in the name of Mitsui Toatsu Chemical Incorporated). Summary of the Invention

[0013] The applicant recognizes that, in general, the use of at least one lubricant allows for easier processing of PEEK polymers during extrusion, thus requiring lower processing temperatures without affecting bulk PEEK properties such as Tg, mechanical properties, and melt strength. Improved processing is associated with a more constant feed rate and a more consistent extrusion process for PEEK. In injection molding, the improvement is associated with improved screw recovery during the plasticizing stage. Using lower processing temperatures also results in less degradation and venting of high-boiling-point impurities present in PEEK, such as residual solvents, monomers, and oligomers, leading to reduced deposits on the die. Due to more consistent processing, the final article has a consistent thickness, with deviations from the nominal thickness of less than 20%.

[0014] However, lubricants are not recommended for applications requiring ultra / high purity.

[0015] In response to the problem of providing polymers suitable for manufacturing systems for transporting ultrapure water (UPW), the applicant unexpectedly discovered that when a very small amount of at least one lubricant is added to the surface of PEEK pellets, the lubricated PEEK pellets not only exhibit more consistent processing (no fluctuations) but also retain bulk properties (e.g., high Tg, good mechanical properties, good melt strength). Moreover, unexpectedly, such PEEK pellets also meet the stringent purity requirements for UPW transport applications, as measured by surface extraction using semiconductor industry standards. Detailed Implementation

[0016] In a first aspect, the present invention relates to a system for conveying ultrapure water (UPW), the system comprising a component having at least one surface intended to contact the UPW, said at least one component comprising a composition comprising: polyetheretherketone (PEEK) and at least one metal selected from Ca, Mg and / or Zn, the amount of which is 5 to 20 ppm based on the amount of PEEK and as measured on the component by inductively coupled plasma optical emission spectroscopy (ICP-OES) after mineralization by ashing in a platinum crucible.

[0017] The at least one component may be selected, for example, from pipes and pipe connectors (also known as “pipe fittings”).

[0018] A pipe connector is a component that can be mechanically attached to one end of a pipe. Pipe connectors are designed to (i) mechanically connect two pipe ends or (ii) mechanically connect one pipe end to another component of a system.

[0019] More preferably, the pipe connector is selected from the group consisting of: adapters, elbows, straight connectors, unions, reducers, tees (also known as "T-fittings"), and crosses (also known as "cross fittings").

[0020] Preferably, the component has a crystallinity level of at least 20%, preferably at least 25%, as measured by DSC based on the first heating scan. The crystallinity level is determined by measuring the heat of fusion based on the first heating scan and assuming that 100% crystalline PEEK has a heat of fusion of 130 J / g.

[0021] In a second aspect, the present invention relates to a conduit for conveying ultrapure water (UPW), the conduit having a surface intended to contact the UPW, the conduit comprising a composition comprising: PEEK and at least one metal selected from Ca, Mg and / or Zn, the amount of which is 5 to 20 ppm based on the amount of PEEK and as measured on the conduit by inductively coupled plasma optical emission spectroscopy (ICP-OES) after mineralization by ashing in a platinum crucible.

[0022] In a third aspect, the present invention relates to a pipe connector comprising a surface intended to contact a UPW (upper pressure vessel), the pipe connector comprising a composition comprising: PEEK and at least one metal selected from Ca, Mg and / or Zn, the amount of which is 5 to 20 ppm based on the amount of PEEK and as measured on the pipe connector by inductively coupled plasma optical emission spectroscopy (ICP-OES) after mineralization by ashing in a platinum crucible.

[0023] The applicant unexpectedly discovered that using lubricated PEEK pellets allows for a reduction in the temperature required to melt and shape the PEEK pellets into parts, while also meeting the stringent purity requirements of UPW delivery applications, such as those measured by surface extraction using semiconductor industry standards.

[0024] Unbound by any theory, the applicant unexpectedly discovered that the components of the system according to the invention have a consistent wall thickness.

[0025] As used herein, the term "consistent wall thickness" is intended to indicate a thickness deviation of the component wall from the nominal wall thickness that is less than 20%, more preferably less than 10%, as measured by X-ray at at least one point, preferably at at least two or more points, of the component wall.

[0026] Consistent wall thickness of components in the system according to the invention is of particular concern when such components are pipes.

[0027] Therefore, the pipe according to the invention has a wall thickness deviation of less than 20%, preferably less than 10%, from the nominal wall thickness, as measured by X-ray at at least one point, preferably at at least two or more points, on the pipe wall.

[0028] Furthermore, the pipe connector of the present invention has a wall thickness deviation of less than 20%, preferably less than 10%, from the nominal wall thickness, as measured by X-ray at at least one point, preferably at at least two or more points, on the pipe connector wall.

[0029] In another aspect, the present invention relates to a system for conveying ultrapure water (UPW), the system comprising at least one component having a surface intended to contact the UPW, said surface being made of granules [lubricated PEEK granules] comprising PEEK and at least one lubricant adhering to at least one region of the outer surface of the granules.

[0030] The components are preferably selected from pipes and pipe connectors as defined above.

[0031] In another aspect, the present invention relates to a conduit for conveying ultrapure water (UPW), the conduit having a surface intended to contact the UPW, said surface being made of granules comprising PEEK and at least one lubricant adhering to at least one region of the outer surface of the granules [lubricated PEEK granules].

[0032] In another aspect, the present invention relates to a pipe connector comprising a surface intended to contact a UPW, said surface being made of granules [lubricated PEEK granules] comprising PEEK and at least one lubricant adhering to at least one region of the outer surface of the granules.

[0033] The system of the present invention also includes at least one means for generating a pressure difference to deliver water, such as a pump.

[0034] In the system of the present invention, the component is prepared by techniques such as (co)extrusion or injection molding.

[0035] Preferably, the pipe is prepared by (co)extrusion.

[0036] Preferably, the pipe connector is manufactured by injection molding.

[0037] The pipe comprises one or more layers. The inner layer, intended to come into contact with water, is made of lubricating PEEK granules as described above.

[0038] According to embodiment (E1), the pipe of the present invention is a single-layer pipe. In this embodiment, the single layer consists of an inner layer (L). It comprises only the layer (L). The single-layer pipe can be prepared by extrusion.

[0039] According to embodiment (E1), the layer (L) corresponds to the wall of the pipe, and the thickness of the layer (L) corresponds to the thickness of the pipe wall. The layer (L) has a consistent wall thickness. Preferably, the layer (L) has a thickness deviation of less than 20%, more preferably less than 10%, from the nominal thickness of the layer (L), as measured by X-ray at at least one point in the pipe, preferably at at least two or more points.

[0040] According to another embodiment (E2), the pipe of the present invention is a multilayer pipe. In this embodiment, the pipe includes more than one layer and the layer (L) is an inner layer (L). For example, the pipe may include a layer (L) and an outer layer. According to embodiment (E2), since the layers other than the layer (L) are not intended to come into contact with water, there is a small risk of water contamination by molecules leaching from these layers. Therefore, this / these layers other than the layer (L) may thus contain at least one filler and / or at least a plastic additive. The multilayer pipe can be prepared by co-extrusion or by overmolding other layers around the layer (L).

[0041] According to embodiment (E2), layer (L) and layers other than layer (L) correspond to the wall of the pipe, and the thickness of layer (L) plus the thickness of layers other than layer (L) corresponds to the thickness of the pipe wall. Preferably, the multilayer pipe has a wall thickness deviation of less than 20%, more preferably less than 10%, from the nominal wall thickness, as measured by X-ray at at least one point in the pipe, preferably at at least two or more points.

[0042] The layers other than layer (L) may contain at least one thermoplastic polymer, at least one filler and / or at least one plastic additive, particularly selected from the group consisting of: colorants (e.g., dyes and / or pigments), impact modifiers, UV stabilizers, heat stabilizers, antioxidants, internal and / or external lubricants, flame retardants, antistatic agents, antiblocking agents and combinations thereof.

[0043] More specifically, according to embodiment (E2), the conduit of the present invention includes:

[0044] - An inner layer (or wall) (L) intended to be in contact with water, said layer (L) being made of lubricated PEEK granules as defined above;

[0045] - At least one other layer, which is made of or includes a polymer composition comprising: at least one polymer as defined herein (P) and (i) at least one filler and / or (ii) at least one plastic additive, particularly selected from the group consisting of: colorants (e.g., dyes and / or pigments), impact modifiers, UV stabilizers, heat stabilizers, antioxidants, internal and / or external lubricants, flame retardants, antistatic agents, antiblocking agents, and combinations thereof.

[0046] The pipes of the present invention can be used to transport UPW because the layer (L) intended to be in contact with water is made of the lubricating PEEK granules disclosed above.

[0047] The characteristics of the pipeline can be described by the amount of eluted impurities given below.

[0048] The pipeline accommodates UPW and / or is characterized by the amount of eluted impurities given below.

[0049] SEMI F40 and SEMI F57 are manufactured by SEMI ®The Association, 673 S. Milpitas Blvd., Milpitas, CA 95035 (USA) edited standards that are generally followed to test polymer materials and components used in UPW systems to assess whether the material is suitable for use without contaminating the UPW. According to these standards, the following protocol (p1) can be used to measure the amount of elution impurities:

[0050]

[0051] The pipeline of the present invention enables, following the above-described scheme, the amount of impurities (Imp) released from the layer (L) after contacting the layer (L) with the UPW at 85°C for 7 days to be less than the values ​​indicated in the table below:

[0052]

[0053] The amount of impurities eluted is expressed in µg / m² of the surface area of ​​the layer (L) in contact with water. 2 express.

[0054] The diameter of the pipe is typically between 1 and 200 mm. More specifically, the diameter can be between 20 and 150 mm.

[0055] The length of the pipe is typically a maximum of 100 m. More specifically, the length can be a maximum of 50 m.

[0056] The pipe connector of the present invention can be used to transport UPW because the surface intended to come into contact with water is made of the lubricating PEEK granules disclosed above.

[0057] SEMI F40 and SEMI F57 are standards that can be used to characterize pipe connectors. According to these standards, the following procedure (p2) can be used to measure the amount of eluted impurities:

[0058]

[0059] The pipe connector of the present invention enables, following the above-described scheme, the elution amount of impurities (Imp) released from the surface in contact with the UPW to be less than that indicated in µg / m in the table below. 2 The values ​​of eluted impurities represented by the surface of the leaching zone:

[0060]

[0061] In the system according to the invention, the at least one component contains some residues from the lubricant, such as calcium, magnesium, or zinc, and unexpectedly, these residues do not affect the level of surface-extractable impurities (cations, TOC) that are of concern to the semiconductor industry.

[0062] Preferably, the amount of Ca, Mg and / or Zn in the component is in the range of 7 to 18 ppm, as measured by ICP-OES (inductively coupled plasma optical emission spectroscopy) on the component after mineralization by ashing in a platinum crucible.

[0063] In another aspect, the present invention relates to a method for manufacturing a component for conveying ultrapure water (UPW), said component preferably selected from pipes or pipe connectors, the method comprising:

[0064] (a) Providing granules comprising PEEK and at least one lubricant adhering to at least one region of the outer surface of the granules [lubricated PEEK granules],

[0065] (b) Melting the lubricated PEEK pellets to provide molten pellets, and

[0066] (c) The molten granules are shaped into a component for conveying at least one UPW.

[0067] Preferably, the forming step (c) can be performed by methods such as extrusion or injection molding. The method can be appropriately selected based on the part to be formed.

[0068] In another aspect, the present invention relates to the use of granules comprising PEEK and at least one lubricant on at least one region of the outer surface of the granules for manufacturing components for conveying ultrapure water, the components preferably being selected from pipes and pipe connectors.

[0069] There are no restrictions on the methods used to manufacture PEEK granules for lubrication.

[0070] Preferably, this type of lubricated PEEK granules is manufactured by a method comprising the following steps:

[0071] (i) Provide granules containing PEEK and free of any lubricant, and

[0072] (ii) Contact at least one region of the outer surface of the PEEK-containing granules with at least one lubricant.

[0073] More preferably, the contact step (ii) is carried out by dry mixing.

[0074] Advantageously, the lubricant is selected from compounds that degrade at processing temperatures.

[0075] As used herein, “degradation” means that the lubricant exhibits a weight loss of 15% or more as measured by thermogravimetric analysis (TGA) at 300°C.

[0076] Preferably, the lubricant is a low-melting-point hydrocarbon-based lubricant, more preferably characterized by a melting point below 250°C, or even more preferably below 200°C.

[0077] Preferably, the lubricant is based on saturated hydrocarbons. More preferably, the lubricant is selected from fatty acid salts, and even more preferably from salts of saturated fatty acids having 10-20 carbon atoms.

[0078] Preferably, the lubricant is selected from calcium stearate, calcium palmitate, magnesium stearate, magnesium palmitate, zinc stearate, or zinc palmitate. More preferably, the lubricant is selected from calcium stearate, calcium palmitate, zinc stearate, or zinc palmitate; even more preferably, it is selected from calcium stearate or calcium palmitate. Calcium stearate is the most preferred.

[0079] Preferably, the lubricated PEEK granules have a diameter between 0.9 and 4.5 mm, more preferably between 1.9 and 3.2 mm.

[0080] Preferably, the lubricated PEEK pellets have a length between 1.5 and 4.8 mm, more preferably between 2.2 and 3.5 mm.

[0081] The diameter and length of the pellets can be measured using any device. For example, calipers can be used to measure the diameter and length of the pellets.

[0082] Preferably, the lubricating PEEK pellets contain a lubricant in an amount of 25 to 500 ppm, more preferably 50 to 250 ppm, and even more preferably 75 to 125 ppm based on PEEK.

[0083] Preferably, the lubricating PEEK granules contain at least 50 wt.%, more preferably at least 60 wt.%, 70 wt.%, 85 wt.%, 95 wt.%, or 99.9 wt.% of PEEK based on the total weight of the granules.

[0084] Advantageously, the lubricating PEEK granules consist of a PEEK amount of 100 wt.% based on the total weight of the granules.

[0085] When the amount of PEEK is less than 100 wt.%, the lubricating PEEK granules may contain at least one other polymer. Such at least one other polymer may be selected from polysulfone (PSU), polyphenylsulfone (PPSU), polyetherimide (PEI), and one or more other polyaryl ether ketones (PAEK).

[0086] Each of the at least one other polymer may be present in an amount ranging from 0.1 wt.% to 5 wt.%, 15 wt.%, 30 wt.%, 40 wt.%, or 50 wt.% based on the total weight of the pellets.

[0087] When step (c) is performed via extrusion, the PEEK is characterized by an appropriately selected range of number-average molecular weight (Mn) and / or weight-average molecular weight (Mw), which allows for a trade-off between melt strength, ductility, and low viscosity for ease of processing. This selection also contributes to consistent processing.

[0088] Advantageously, the PEEK has an Mn of above 42,000, preferably above 43,000, more preferably above 44,000, as measured by GPC at 160°C using polystyrene (PS) standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0089] Preferably, the PEEK has an Mn content of less than 58,000, preferably less than 57,000, and more preferably less than 56,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0090] Advantageously, the PEEK has a Mw greater than 90,000, more preferably greater than 95,000, and even more preferably greater than 97,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0091] Preferably, the PEEK has a Mw of less than 125,000, more preferably less than 120,000, even more preferably less than 115,000, and still more preferably less than 110,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0092] When step (c) is performed via injection molding, the PEEK is characterized by an appropriately selected range of number-average molecular weight (Mn) and / or weight-average molecular weight (Mw), which allows for a trade-off between melt strength, ductility, and low viscosity for ease of processing. This selection also contributes to consistent processing.

[0093] Advantageously, the PEEK has an Mn of greater than 29,000, preferably greater than 30,000, and most preferably greater than 31,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0094] Preferably, the PEEK has an Mn content of less than 54,000, more preferably less than 53,000, and even more preferably less than 52,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0095] Advantageously, the PEEK has a Mw greater than 60,000, preferably greater than 62,000, more preferably greater than 63,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0096] Preferably, the PEEK has a Mw of less than 110,000, more preferably less than 108,000, and even more preferably less than 107,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

[0097] Unbound by any theory, the selection of the above-mentioned Mn and Mw ranges allows for good melt strength and high ductility, both of which are critical in this application, while minimizing viscosity for ease of processing.

[0098] Preferably, the PEEK contains at least 85 mol%, more preferably at least 90 mol%, even more preferably at least 95 mol%, at least 98 mol%, at least 99 mol%, and even most preferably 100 mol%, of the formula (R). PEEK Units of )

[0099] (R PEEK )

[0100] Preferably, when PEEK contains less than 100 mol% of an ingredient having the formula (R) as expressed above. PEEK When the unit is ), the PEEK may contain at least one unit having the following formula (KA) to (KM) at a maximum of 1 mol%, a maximum of 2 mol%, a maximum of 5 mol%, a maximum of 10 mol%, or a maximum of 15 mol%.

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107] Each R' is independently selected from halogens, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali metal or alkaline earth metal sulfonates, alkyl sulfonates, alkali metal or alkaline earth metal phosphonates, alkyl phosphonates, amines, and quaternary ammonium; and each j' is independently 0 or an integer from 1 to 4.

[0108] In yet another aspect, the present invention relates to a method for conveying UPW, wherein at least one pipe or pipe connector as defined above is used. Experimental Section

[0109] raw materials

[0110] Hydroquinone, photographic grade, is obtained from Eastman, USA, and contains 0.38 wt% moisture, which is used to adjust for the load weight. All indicated weights include moisture.

[0111] 4,4'-Difluorobenzophenone, polymer grade (99.8%+), is obtained from Malwa, India, and shows to contain an oxidizing agent with a concentration of less than 3.0 µmol TiCl3 / g as measured by redox titration as described in WO 2012 / 001131.

[0112] Diphenyl sulfone (polymer grade) was obtained from Proviron (99.8% pure).

[0113] Sodium carbonate, light soda ash, was obtained from Solvay SA, France.

[0114] Potassium carbonate, with d90 < 45 µm, was obtained from Armand Products.

[0115] The lithium chloride (anhydrous grade) was obtained from Acros.

[0116] Calcium stearate is obtained from Sigma Aldrich.

[0117] Determination of Mn and Mw by gel permeation chromatography (GPC)

[0118] The molecular weight of the samples was determined using a PL 220 high-temperature GPC system under the conditions described in Table 1 below.

[0119] Table 1

[0120]

[0121] The sample concentration was approximately 0.20% wt. / vol. in the mobile phase. The sample was dissolved completely by heating at approximately 190°C with magnetic stirring. The GPC method used was similar to ASTM D5296 but modified due to the need for different solvents, GPC columns, and conditions. Calibration was performed using 11 narrow calibration standards of polystyrene (purchased from Agilent Technologies, with peak molecular weight ranges from 1,210,000 to 580).

[0122] Determination of the crystallinity level of the final product

[0123] The heat of fusion is determined in a differential scanning calorimeter (DSC) according to ASTM D3418-03, E1356-03, E793-06, and E794-06, based on the endothermic melting of the first heating scan.

[0124] The procedures used in this paper are detailed below: A TA instrument DSC Q20 was used, with nitrogen (99.998% purity, 50 mL / min) as the carrier gas. Temperature and heat flow rate calibration were performed using indium. Sample volumes ranged from 5 to 7 mg. Weights were recorded to ±0.01 mg. Heating cycles were:

[0125] First heating cycle: 20.00°C / min, from 30.00°C to 400.00°C, isothermal at 400.00°C for 1 min;

[0126] First cooling cycle: 20.00°C / min, from 400.00°C to 30.00°C, isothermal for 1 min;

[0127] The second heating cycle: at 20.00°C / min, from 30.00°C to 400.00°C, and isothermal at 400.00°C for 1 min.

[0128] The melting of the composition is considered as the area above a linear baseline drawn from 220°C to temperatures above the last endothermic temperature. Any exothermic reaction associated with cold crystallization is accounted for by the total heat of fusion measured based on the first heating scan. % crystallinity is defined as 100 × heat of fusion (J / g) / 130 (J / g).

[0129] Determination of surface extractable impurities according to SEMI-40

[0130] Fill sample containers (each containing one substrate) with ultrapure water (milliQ) for 2 minutes. Then drain the water. Repeat 10 times. For actual leaching tests, on the 11th time, fill the container with just enough water to cover the substrate. Perform three tests for each substrate type.

[0131] Meanwhile, five “blank” glass containers and five “blank” HDPE containers, each containing the same amount of ultrapure water but without a substrate, were subjected to the same procedure as the bottles containing the substrate. These are the “procedure blanks”.

[0132] The containers holding the substrate and the program blank container were then placed in an oven at 85°C for 7 days. They were stirred once a day except on weekends.

[0133] After 7 days of leaching, the sample solution was transferred to a clean container for TOC, metal, and anion measurements. Immediately after transfer, the solution for metal determination was slightly acidified with concentrated HNO3 to stabilize the metals.

[0134] Surface extractable metals were measured using a Thermo Element 2 instrument via high-resolution ICP-MS (SEMI F57 list).

[0135] Surface-extractable anions (SEMIF57 list) were measured using ion chromatography (IC) with a Dionex ICS-5000 instrument.

[0136] The TOC (Total Organic Carbon) was measured using a Shimadzu TOC-L instrument as the difference between TC (Total Carbon) and TIC (Total Inorganic Carbon).

[0137] Measurement of tube thickness

[0138] The thickness of the tube was measured using an X-ray system with a Zumbach RAYEX S XT110 instrument.

[0139] The tube to be tested is passed through a measurement unit where it is irradiated for a short period of time along both the horizontal and vertical axes using an X-ray beam. X-ray sensitive detectors on opposite sides measure the intensity of the incident light during the exposure time for each source. Since the product absorbs light to varying degrees (depending on the layer thickness), an absorption profile is obtained for each axis. From the absorption profiles, reconstructed images of the diameter, thickness, out-of-roundness, and eccentricity can be calculated and created. The system has a resolution of 5 micrometers.

[0140] Elemental impurities such as calcium and magnesium in PEEK products were determined by ICP-OES.

[0141] Place a clean, dry platinum crucible on an analytical balance and zero the balance. Weigh half to three grams of the tubular sample into a small dish and record the weight to 0.0001 g. Place the crucible containing the sample in a flame-protected furnace (ThermoScientific Thermolyne F6000 programmable furnace). Gradually heat the furnace to 525°C and maintain this temperature for 10 hours to allow the sample to dry ashed. After ashing, cool the furnace to room temperature and remove the crucible from the furnace and place it in a fume hood. Dissolve the ash in dilute hydrochloric acid. Transfer the solution to a 25 mL volumetric flask using a polyethylene pipette. Rinse the crucible twice with approximately 5 mL of ultrapure water (R < 18 MΩcm) and add the washings to the volumetric flask for quantitative transfer. Add ultrapure water to the flask to a total of 25 mL. Place the stopper on top of the flask and shake thoroughly to mix the contents.

[0142] ICP-OES analysis was performed using a Perkin-Elmer Optima 8300 dual-view inductively coupled plasma optical emission spectrometer. The spectrometer was calibrated using a set of NIST traceable multi-element mixture standards with analyte concentrations ranging from 0.0 to 10.0 mg / L. Linear calibration curves were obtained across a range of concentrations, with correlation coefficients better than 0.9999 for each of the 48 analytes. Standards were run before and after every ten samples to ensure instrument stability. Results were reported as the average of three replicates. The concentration of elemental impurities in the samples was calculated using the following formula:

[0143] A = (B C) / (D)

[0144] in:

[0145] A = Element concentration in the sample, expressed in mg / kg (= wt.ppm)

[0146] B = elemental concentration in solution as measured by ICP-OES, in mg / L.

[0147] C = Volume of solution analyzed by ICP-OES, in mL

[0148] D = The sample weight in grams used in the program.

[0149] Example 1: Preparation of PEEK pellets

[0150] In a 1000 mL four-necked reaction flask equipped with a stirrer, an N2 inlet pipe, a Claisen adapter with a thermocouple inserted into the reaction medium, and a Dean-Stark water separator with a condenser and a dry ice trap, the following substances were introduced: 343.630 g of diphenyl sulfone, 77.121 g of hydroquinone, and 153.866 g of 4,4'-difluorobenzophenone. The contents of the flask were purged under vacuum and then filled with high-purity nitrogen (containing less than 10 ppm of O2). The reaction mixture was then subjected to a constant nitrogen purging (60 mL / min).

[0151] The reaction mixture was slowly heated to 150°C. At 150°C, a mixture of 76.939 g of Na₂CO₃ and 0.484 g of K₂CO₃ was added to the reaction mixture over 30 minutes using a powder dispenser. At the end of the addition, the reaction mixture was heated to 320°C at a rate of 1°C / min. After 73 minutes at 320°C, the reaction was terminated in three stages: 18.336 g of 4,4'-difluorobenzophenone was added to the reaction mixture while the reactor was purged with nitrogen. After 5 minutes, 1.188 g of lithium chloride was added to the reaction mixture. After 10 minutes, an additional 6.112 g of 4,4'-difluorobenzophenone was added to the reactor and the reaction mixture was maintained at this temperature for 15 minutes.

[0152] The reactor contents were then poured into an SS pan and cooled. The solids were crushed and ground in a grinder (through a 2 mm sieve). Diphenyl sulfones and the salt were extracted from the mixture at room temperature by sequential extraction with acetone and water. The powder was then dried under vacuum at 120°C for 12 hours, yielding 188 g of white powder. The material has a Mn content of 50,000 and a Mw content of 100,000 (PDI = 2.00).

[0153] The powder prepared under the conditions detailed above (but on a larger scale) is granulated by melt processing on a 26 mm diameter Coperion® twin-screw extruder with intermeshing co-rotating sections having an L / D ratio of 48:1. The extruder is equipped with 12 barrel sections, of which barrel sections 2 to 12 are temperature-controlled. The extruder is equipped with a 3-mm diameter single-hole die. The resin feeder feeds into the feed hopper (barrel section 1). During compounding, vacuum ventilation (with a vacuum level of >25 inHg) is applied at barrel section 10 to remove moisture and any possible residual volatiles from the compound. The extrudates from each composition are formed into strips and cooled in a water bath, and then granulated into pellets using a Maag Primo 60 E granulator.

[0154] The granulation conditions are reported in Table 2 below.

[0155] Table 2

[0156]

[0157] Example 2: Addition of lubricant to PEEK pellets

[0158] The granules prepared according to Example 1 were sprinkled with calcium stearate at 100 ppm relative to PEEK and tumbled in a drum for 2 hours to disperse them.

[0159] Example 3: Injection molding

[0160] The granular material obtained according to Example 2 was injection molded into substrates (51 mm x 76 mm x 2.5 mm) on a 150-ton Toshiba molding machine equipped with a 2.3:1 compression ratio screw. The 28 mm barrel had four heating zones, using the conditions detailed in Table 3 below. These substrates were then annealed at 200°C for 3 hours prior to testing.

[0161] Table 3

[0162]

[0163] The surface extractable ions and total organic matter (TOC) of PEEK in Example 2 were measured and are listed in Table 4.

[0164] Table 4

[0165]

[0166] The detected levels match the expected requirements for the delivery of ultrapure water, indicating that the low-melting-point PEEK of the present invention matches the purity requirements of the final application.

[0167] Example 4: Pipe extrusion according to the present invention

[0168] 16 mm PEEK pipes were extruded using a 45 mm extruder. A draw ratio (DDR) of 2.14 was used. The pipes were calibrated using a standard vacuum bath filled with cold water. The pipe thickness was 1.5 mm and was adjusted by throughput and linear velocity. The pellets were dried at 120°C for 4 hours and then fed into the hopper in overflow mode.

[0169] The screw used was a standard three-zone (feed, transition, metering) L / D 26 screw. A nearly flat temperature profile was used, as reported in Table 5.

[0170] Table 5

[0171]

[0172] The resulting pipe has a smooth outer surface and a constant thickness.

[0173] The wall thickness was measured at four points on two axes using an X-ray system over a length of 2 cm.

[0174] The maximum thickness deviation measured was 0.040 mm, which was considered acceptable, and the thickness deviation at no point exceeded 0.315 mm (corresponding to 20% of the nominal pipe thickness).

[0175] The final pipeline was analyzed by ICP-OES and showed that it contained 13 ppm of calcium.

[0176] Example 5: (Comparative) Pipe extrusion of non-lubricated PEEK

[0177] In contrast, following the method disclosed in Example 4 above, pipes were manufactured using PEEK granules, wherein no lubricant was applied to the outer surface of the PEEK granules. A nearly flat temperature profile was used, as reported in Table 6.

[0178] Table 6

[0179]

[0180] The resulting pipe exhibits high thickness deviation.

[0181] It is impossible to manufacture a pipe with a constant thickness. The conical polymer exiting the mold and entering the calibration bath is pulsating. Some breathing effect due to the pellets retracting along the screw can be seen in the hopper.

[0182] The wall thickness was measured at four points on two axes using an X-ray system over a length of 2 cm.

[0183] The maximum thickness deviation measured was 1.08 mm, and the thickness deviations at four points exceeded 0.30 mm (20% of the nominal pipe thickness), which was considered unacceptable. This thickness variation was visually noticeable because the pipe wall is transparent at its thinnest point. This pattern was repeated every 20 cm.

[0184] The final pipeline was analyzed by ICP-OES and showed that it contained 3 ppm of calcium.

Claims

1. A system for conveying ultrapure water (UPW), the system comprising at least one component having a surface intended to contact the UPW, said at least one component comprising a composition comprising polyetheretherketone (PEEK) and at least one metal selected from Ca, Mg and / or Zn, the amount of the metal being 5 to 20 ppm based on the amount of PEEK and as measured on the component by inductively coupled plasma optical emission spectroscopy (ICP-OES) after mineralization by ashing in a platinum crucible.

2. The system according to claim 1, wherein, The component has: - A crystallinity level of at least 20%, as measured by DSC based on the heat of fusion measured according to the first heating scan and assuming that 100% crystalline PEEK has a heat of fusion of 130 J / g; and / or - The thickness deviation of the wall of the component, which differs from the nominal wall thickness by less than 20%, as measured by X-ray at at least one point, preferably at at least two points.

3. The system according to claim 1 or 2, wherein, The at least one component is selected from pipes and pipe connectors.

4. The system according to any one of claims 1 to 3, wherein, The pipe connector is selected from the group consisting of: adapters, elbows, straight connectors, unions, reducers, tees, and crosses.

5. The system according to any one of the preceding claims, wherein, The PEEK contains 100 mol% of the product with the formula (R PEEK Units of ) (R PEEK )。 6. The system according to any one of the preceding claims, wherein, The PEEK contains at least 85 mol%, more preferably at least 90 mol%, and even more preferably at least 95 mol%, at least 98 mol%, and at least 99 mol% of the product having the formula (R). PEEK Units of ) (R PEEK ) as well as At least one unit having the formula (KA) to (KM) with a maximum concentration of 1 mol%, up to 2 mol%, up to 5 mol%, up to 10 mol%, or up to 15 mol%. Each R' is independently selected from halogens, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali metal or alkaline earth metal sulfonates, alkyl sulfonates, alkali metal or alkaline earth metal phosphonates, alkyl phosphonates, amines, and quaternary ammonium; and each j' is independently 0 or an integer from 1 to 4.

7. The system according to any one of claims 1 to 6, wherein, The at least one component has a surface designed to contact the UPW, the surface being made of granules [lubricated PEEK granules] comprising PEEK and at least one lubricant adhering to at least one region of the outer surface of the granules.

8. The system according to claim 7, wherein, The lubricating PEEK granules contain 100 wt.% of PEEK based on the total weight of the granules.

9. The system according to claim 7, wherein, The lubricating PEEK granules comprise at least 50 wt.%, more preferably at least 60 wt.%, 70 wt.%, 85 wt.%, 95 wt.%, or 99.9 wt.%, of PEEK based on the total weight of the granules, and at least one other polymer based on 0.1 wt.% to 5 wt.%, 15 wt.%, 30 wt.%, 40 wt.%, or 50 wt.%, of the total weight of the granules, wherein the at least one other polymer is preferably selected from polysulfone (PSU), polyphenylene sulfone (PPSU), polyetherimide (PEI), or one or more other polyaryl ether ketones (PAEK).

10. A method for manufacturing a component for conveying ultrapure water (UPW), the method comprising: (a) Providing granules comprising PEEK and at least one lubricant adhering to at least one region of the outer surface of the granules [lubricated PEEK granules], (b) Melting the lubricated PEEK pellets to provide molten pellets, and (c) The molten granules are shaped into at least one component for conveying the UPW.

11. The method according to claim 10, wherein, The lubricant is selected from calcium stearate, calcium palmitate, magnesium stearate, magnesium palmitate, zinc stearate, or zinc palmitate.

12. The method according to claim 10 or 11, wherein, The forming step (c) is performed by extrusion or injection molding.

13. The method according to claim 12, wherein, Step (c) is performed by extrusion and the PEEK has: - A number-average molecular weight (Mn) greater than 42,000, preferably greater than 43,000, more preferably greater than 44,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50); and / or a number-average molecular weight (Mn) less than 58,000, preferably less than 57,000, more preferably less than 56,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50); and / or - Weight-average molecular weight (Mw) greater than 90,000, more preferably greater than 95,000, even more preferably greater than 97,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50), and / or less than 125,000, more preferably less than 120,000, even more preferably less than 115,000, and still more preferably less than 110,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

14. The method according to claim 13, wherein, The component is selected from pipes.

15. The method according to claim 12, wherein, Step (c) is performed by injection molding and the PEEK has: - A number-average molecular weight (Mn) greater than 29,000, preferably greater than 30,000, more preferably greater than 31,000, as measured by GPC at 160°C using a PS standard in 1,2,4-trichlorobenzene:phenol (50:50); and / or a number-average molecular weight (Mn) less than 54,000, more preferably less than 53,000, even more preferably less than 52,000, as measured by GPC at 160°C using a PS standard in 1,2,4-trichlorobenzene:phenol (50:50); and / or - Weight-average molecular weight (Mw) greater than 60,000, preferably greater than 62,000, more preferably greater than 63,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50), and / or less than 110,000, more preferably less than 108,000, even more preferably less than 107,000, as measured by GPC at 160°C using PS standards in 1,2,4-trichlorobenzene:phenol (50:50).

16. The method according to claim 15, wherein, The component is selected from pipe connectors.

17. The method according to any one of claims 10 to 16, wherein, The lubricated PEEK granules: - Having a diameter between 0.9 and 4.5 mm and / or a length between 1.5 and 4.8 mm; and / or - The lubricant contains 25 to 500 ppm of PEEK and at least 50 mol% of PEEK based on the total weight of the granules.

18. A conduit for conveying ultrapure water (UPW), the conduit having a surface intended to contact the UPW, the conduit comprising a composition comprising PEEK and at least one metal selected from Ca, Mg and / or Zn, the amount of the metal being 5 to 20 ppm based on the amount of PEEK and as measured on the conduit by inductively coupled plasma optical emission spectroscopy (ICP-OES) after mineralization by ashing in a platinum crucible.

19. The pipe of claim 18, wherein the pipe has a wall thickness deviation of less than 20% from the nominal wall thickness, as measured by X-ray at at least one point on the wall of the pipe.

20. A pipe connector including a surface intended to contact a UPW, the pipe connector comprising a composition comprising PEEK and at least one metal selected from Ca, Mg and / or Zn, the amount of which is 5 to 20 ppm based on the amount of PEEK and as measured on the pipe connector by inductively coupled plasma optical emission spectroscopy (ICP-OES) after mineralization by ashing in a platinum crucible.

21. The pipe connector of claim 20, wherein the pipe connector has a wall thickness deviation of less than 20% from the nominal wall thickness, as measured by X-ray at at least one point on the wall of the pipe connector.

22. Use of granules containing PEEK and at least one lubricant on at least one region of the outer surface of the granules for manufacturing components for conveying UPW.

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