Applicator for high-viscosity materials

Abstract

A coating applicator for applying a high-viscosity coating to a large surface area is disclosed. The coating applicator facilitates the ability to provide a thickness-controlled coating by applying a high-viscosity material at high speed to a large surface area while minimizing air entrapment.

Description

Technology Field

[0001] The present disclosure relates to an applicator for high-viscosity materials and a method for applying a thin layer of a high-viscosity material, such as a sealant barrier coating. The applicator applies a high-viscosity material, such as a sealant, at high speed over a wide area while minimizing air entrapment, thereby providing a thin coating with a controlled thickness. Background Technology

[0002] The application of low-viscosity materials over large surface areas can be achieved by spraying the material into an airflow or by atomizing and entraining it. This is a highly efficient process for coating large surfaces. However, atomizing and spraying high-viscosity materials is difficult. Air trapping is a problem, which negatively affects the properties of the cured sealant. Insufficient atomization can result in improper control of the thickness and uniformity of the surface coverage. Poor thickness control can affect the thixotropic properties of the surface coating. Solvents and rheological agents may be added to reduce viscosity. However, the use of solvents increases the volatile organic compound (VOC) content of the formulation, which can increase environmental impact and health risks for personnel.

[0003] There is a need for an apparatus and method to apply a high-viscosity sealant to a large surface area with high efficiency and to provide a coating with uniform thickness and coverage that has desired aesthetic and functional properties. means of solving the problem

[0004] According to the present invention, an extrusion applicator comprises: (a) an adapter section including a proximal end, a distal end, and an adapter channel; (b) a transition section mechanically coupled to the adapter section and including a proximal end and a distal end—wherein the transition section defines an internal transition channel including a width and a height; said width of the transition channel increases from a transition inlet to a transition outlet; and said height of the transition channel decreases from a transition inlet to a transition outlet—; and (c) a nozzle section mechanically coupled to the transition section and including a proximal end, a distal end, and a nozzle outlet, wherein the nozzle section defines an internal nozzle channel including a width and a height; and said nozzle channel includes a flow control section adjacent to the proximal end and a pressure control section adjacent to the distal end.

[0005] According to the present invention, a method for coating a substrate surface comprises the steps of: pumping a curable coating composition into the adapter section of an extrusion applicator according to the present invention; positioning the nozzle outlet adjacent to the surface; and moving the nozzle outlet across the surface to apply the curable coating to the surface.

[0006] According to the present invention, a method for applying a coating comprises the steps of: saturating a foam cover of a roller with a curable coating composition—wherein the roller comprises a cylindrical core; and a foam cover surrounding the core—; repeatedly rolling the saturated foam cover over a substrate surface to apply a layer of the curable coating composition to a substrate surface; and curing the applied curable coating composition to provide a cured coating, wherein the curable coating composition is characterized by a viscosity of 1,000 cp to 10,000 cp, wherein the viscosity is determined using a Brookfield CAP 2000 viscometer equipped with a No. 6 spindle at a speed of 300 rpm and a temperature of 25°C. Brief explanation of the drawing

[0007] The drawings described herein are for illustrative purposes only. The drawings are not intended to limit the scope of the disclosure. FIG. 1 shows a perspective view of an extrusion applicator provided by the present disclosure. Specific details for implementing the invention

[0008] For the purposes of the following detailed description, it should be understood that the embodiments provided by this disclosure may assume various alternative variations and sequences of steps, except as otherwise expressly stated. Furthermore, except in any example of operation or otherwise indicated, all numbers expressing the amount of a component used, for example in the specification and claims, should be understood to be modified in all cases by the term "approximately." Accordingly, unless otherwise stated, the numerical parameters presented in the following specification and appended claims are approximations that may vary depending on the desired properties to be obtained by the present invention. At a minimum, each numerical parameter should be interpreted by applying general rounding techniques, taking into account at least the reported significant digits, without attempting to limit the application of the doctrine of equivalents to the scope of the claims.

[0009] Although the numerical ranges and parameters presenting the broad scope of the present invention are approximations, the numerical values ​​presented in specific embodiments are reported as accurately as possible. However, all numerical values ​​inherently contain certain errors that inevitably occur due to standard variations found in the corresponding test measurements.

[0010] Additionally, any numeric range cited in this specification should be understood to be intended to include all sub-ranges contained therein. For example, the range “1 to 10” is intended to include all sub-ranges between (inclusive of) the mentioned minimum value 1 and the mentioned maximum value 10, that is, sub-ranges where the minimum value is greater than or equal to 1 and the maximum value is less than or equal to 10.

[0011] Applicators for applying high-viscosity materials, such as sealants, to large surface areas include extrusion applicators and roller applicators. The applicators can apply high-viscosity materials to large surface areas at high speed with a controlled thickness while minimizing air entrapment.

[0012] The applicator provided by the present disclosure includes an extrusion applicator. An exemplary perspective view of an extrusion applicator provided by the present disclosure is shown in FIG. 1.

[0013] The extrusion applicator illustrated in FIG. 1 includes an adapter section (101), a transition section (102), and a nozzle section (103).

[0014] The adapter section (101) connects the applicator to a source of material. Examples of material sources include a material reservoir, a material supply line, a mixing device, or any combination of the foregoing. The material source may be supplied to the applicator under pressure, for example, between 10 psi and 100 psi. The material source and the pump used to apply pressure may be a closed system to minimize or prevent air trapping. The adapter section may be connected to a source of coating composition via a hose that can be secured to the adapter section using, for example, a threaded or press-fit coupling. The adapter section (101) includes a proximal end (101a) and a distal end (101b). The wall of the adapter section defines an internal channel (101c).

[0015] Proximal refers to the relative position of the element facing the inlet of the adapter section and away from the nozzle exit. Distal refers to the relative position of the element away from the adapter inlet and facing the nozzle exit of the applicator.

[0016] The transition section (102) is mechanically coupled to the adapter section (101). The transition section (102) includes laterally diverging dimensions having internal dimensions that converge in the longitudinal direction. The dimensions of the diverging section can be selected based on the desired coverage area. The convergent dimensions cause shear in the material. When a shear-thinning material is used, the shear caused by the material flow can reduce the viscosity of the material, thereby facilitating the ability to apply a uniform layer of material laterally. The convergent dimensions can be configured to pull the material to a thickness close to the thickness of the applied material layer.

[0017] The transition section (102) has a proximal end (102a) coupled to the distal end (102b) of the adapter section (101b). The transition section (102) includes the wall of the transition section defining the distal end (102b) and the internal channel (102c). As shown in FIG. 1, the width or lateral dimension of the channel (102c) increases from the proximal end (102a) to the distal end (102b), and the height of the channel (102c) decreases from the proximal end (102a) to the distal end (102b).

[0018] The nozzle section (103) includes an opening that matches the dimensions of the opening at the distal end (102b) of the transition section (102). The nozzle section (103) includes a proximal end (103a) coupled to the distal end (102b) of the transition section (102). The nozzle section (103) includes a proximal end (103b), and the wall of the nozzle section (103) defines an internal channel (103c). The distal end (103c) of the nozzle section (103) includes a nozzle outlet (103d). The nozzle outlet (103d) may have a height of, for example, 0.1 mm to 10 mm, 0.2 mm to 8 mm, 0.5 mm to 6 mm, or 1 mm to 4 mm. The nozzle outlet may have a height of, for example, less than 15 mm, less than 10 mm, less than 8 mm, less than 6 mm, less than 4 mm, less than 2 mm, or less than 1 mm. The nozzle outlet may have a height of, for example, greater than 0.1 mm, greater than 1 mm, greater than 2 mm, greater than 4 mm, greater than 6 mm, greater than 8 mm, or greater than 10 mm. The nozzle outlet (103d) may have a width of, for example, 25 mm to 500 mm, 50 mm to 400 mm, or 100 mm to 300 mm. The nozzle outlet may have a rectangular shape. The nozzle outlet may have a width of, for example, less than 500 mm, less than 400 mm, less than 300 mm, less than 200 mm, less than 100 mm, less than 50 mm, less than 40 mm, less than 30 mm, less than 20 mm, or less than 10 mm. The nozzle outlet may have a width of, for example, more than 10mm, more than 20mm, more than 30mm, more than 40mm, more than 50mm, more than 100mm, more than 200mm, more than 300mm, more than 400mm, and more than 500mm.

[0019] The nozzle outlet (103d) is adjustable to accommodate different application material thicknesses. The height, width, or both height and width of the nozzle outlet (103d) are adjustable. The dimensions of the nozzle outlet (103d) can be adjusted automatically or manually.

[0020] The nozzle section (103) may have a uniform width such that the width of the internal channel is the same at both the proximal and distal ends of the nozzle section (103). The height of the internal channel of the nozzle section may be the same at the proximal end (103a) and the distal end (103b) of the nozzle section (103). The height of the internal channel of the nozzle section may differ at the proximal end (103a) and the distal end (103b) of the nozzle section (103).

[0021] The nozzle section (103) may include a flow control section (104) and a pressure control section (105). The flow control section (104) may be located near the distal end (102b) of the switching section (102). The pressure control section (105) may extend from the flow control section (104) to the distal end (103b) of the nozzle section (103).

[0022] The flow control section (104) may be configured to provide a laminar flow of a viscous composition over the entire width of the nozzle section. The flow control section (104) may include a plurality of parallel channels. Each of the plurality of parallel channels may have a width of, for example, 1 mm to 10 mm, 1 mm to 8 mm, 1 mm to 6 mm, or 1 mm to 4 mm. The channels may have any suitable cross-sectional profile. For example, the channels may have a square, rectangular, elliptical, or diamond-shaped cross-sectional profile. Each of the plurality of channels may have the same dimensions, or at least some of the channels may have different dimensions from other channels. The plurality of parallel channels may extend over the width of the nozzle section (103). The plurality of parallel channels may include, for example, 2 to 100 parallel channels, 5 to 90 parallel channels, 10 to 80 parallel channels, or 20 to 60 parallel channels.

[0023] Among the plurality of parallel flow control channels, the channel may have a uniform cross-sectional profile over the entire length of the channel, or the cross-sectional profile may vary continuously or discontinuously over the entire length of the channel. For example, the cross-sectional profile may taper toward the distal end, such as a conical shape. The plurality of parallel flow control channels may have a length of, for example, 1 mm to 30 mm, 2 mm to 28 mm, 5 mm to 25 mm, or 10 mm to 20 mm.

[0024] The channel may be dimensioned and shaped to provide secondary shear thinning to facilitate uniform flow across the width of the applicator outlet nozzle and / or to facilitate application.

[0025] Each of the plurality of parallel flow control channels is coupled to an internal channel of the pressure control section (105) of the nozzle section (103). The pressure control section includes a substantially open channel that couples the plurality of parallel flow control channels to the nozzle outlet (103d). The channel of the pressure control section may have a constant width. The height of the channel of the pressure control section may be uniform or tapered toward the nozzle outlet. The channel of the pressure control section may be tapered to be wider at the nozzle outlet than at the interface with the flow control section, or narrower at the nozzle outlet than at the interface with the flow control section.

[0026] The applicator pressure control section may include one or more support structures (107). The support structures may provide physical integrity to the nozzle section and the pressure control section. The support structures may prevent the pressure control section from collapsing and / or expanding and may help ensure a uniform thickness of the applied layer.

[0027] The height of the internal channel of the nozzle section may be the same at the proximal end (103a) and the distal end (103b) of the nozzle section (103), and the thickness of the applied layer may be maintained over the entire width of the nozzle exit.

[0028] The lateral dimensions of the nozzle exit can be selected according to the thickness and / or width of the layer of sealant to be applied to the substrate surface.

[0029] The height dimension of the exit slit can be selected according to the thickness of the coating to be applied.

[0030] The nozzle section may be designed to be detachable. Interchangeable release sections may be used to apply coatings of different thicknesses and / or different widths.

[0031] The nozzle section is adjustable. For example, the distal end of the nozzle section can be configured so that the dimensions of the nozzle exit can be adjusted manually or automatically, either continuously or discontinuously. The adjustable dimensions can facilitate the function of changing the thickness of the material layer applied to a selected area of ​​the substrate surface.

[0032] The extrusion applicator may include a mating section (not shown). The mating section may facilitate the connection between the transition section (102) and the nozzle section (103). The mating section may include a mechanism for separably connecting the transition section and the nozzle section. The mating section may include a mechanism that provides a function for rotatably adjusting the angle between the transition section and the nozzle section.

[0033] The transition section and the nozzle section can be configured to allow for adjustable angles defined at the intersection between the transition section and the nozzle section. The connection can be configured to allow for continuous or discontinuous angle adjustment. The ability to change angles enables easy access to surface areas that are difficult to reach with a straight configuration.

[0034] The extrusion applicator may include a removable external closure that retains all or part of the applicator. The closure may protect the applicator and / or protect surfaces and operators from leakage. The closure is removable.

[0035] The extrusion applicator may be manufactured from any suitable material to achieve the intended purpose. For example, the applicator may be manufactured from thermoplastic materials, thermosetting materials, metals, alloys, composites, or any combination thereof. The material and thickness of the wall of the section of the applicator may be selected to withstand the extrusion pressure. The nozzle section or the nozzle section adjacent to the nozzle exit may be flexible. A flexible nozzle section adjacent to the nozzle exit may facilitate the nozzle exit's ability to conform to a lower surface having various curvatures. The nozzle section and the nozzle exit may be substantially flat, or may have curvature or other cross-sectional shapes to facilitate the nozzle exit's ability to provide a layer of material of uniform thickness on a non-planar surface.

[0036] The inner wall of the extrusion applicator defining the internal channel can be coated with a layer of shear-thinning material. Examples of coatings that promote the ability of a viscous curable composition extruded by the applicator include fluorocarbon coatings.

[0037] One or more sections of the applicator may be heated to facilitate the ability of the viscous curable composition to be extruded by the applicator. The extrusion applicator may be heated using any suitable heating device. For example, a thermoelectric heating element may be applied to one or more external surfaces of the applicator, such as, for example, a transition section and / or an ejection section.

[0038] The extrusion applicator can be heated only in the discharge section or near the exit slit, thereby reducing the viscosity of the material immediately before and / or during application to the surface. This reduction in viscosity can facilitate the ability to apply a laterally uniform coating with a uniform film thickness.

[0039] Slightly heating the outer surface of the extrusion applicator may help promote laminar flow of the material through the device.

[0040] The extrusion applicator may be a portable device or may be integrated into a robotic system. For example, the extrusion applicator provided by the present disclosure may be integrated into an automation system including a gantry, a robotic arm, and a processor.

[0041] The extrusion applicator may include flow sensors disposed within one or more sections. Flow sensors may be used to control the flow rate of a curable composition through the extrusion applicator. The flow rate may be monitored and used to control the thickness of the applied material composition.

[0042] Sealant applicators may include roller applicators. For example, a specific roller used for applying a coating can be adapted to apply viscous sealant materials at high speeds over a large surface area while minimizing bubble capture and solvent use.

[0043] The roller applicator may have a single, split, or double configuration and may be of any suitable length. The length may be selected to match the dimensions to which the curable coating composition is applied. For example, the length of the roller applicator may be 2 inches to 12 inches (5.1 cm to 30.5 cm), 3 inches to 10 inches (7.6 cm to 25.4 cm), or 4 inches to 9 inches (10.2 cm to 22.9 cm). The roller applicator may have a solid core or a core perforated with holes and / or slits so that sealant material can be fed into the core and exit through the perforations of the core. The core may have a cylindrical shape.

[0044] A foam sheath can cover the core. The foam sheath ensures a uniform flow of sealant material throughout the entire foam layer.

[0045] Any suitable foaming material may be used. Examples of suitable foaming materials include polyester, polyurethane, and combinations thereof.

[0046] The foamed outer shell may have a nap thickness of, for example, 0.1 inch to 0.5 inch (2.54 mm to 12.7 mm), for example, 0.125 inch to 0.4 inch (3.18 mm to 10.16 mm), or 0.15 inch to 0.3 inch (3.81 mm to 7.62 mm).

[0047] The foam outer shell is, for example, 1.5 lb / ft 3 Up to 5 lb / ft 3 (24.0kg / m 3 Up to 80.1 kg / m² 3 ), for example, 2.0 lb / ft 3 Up to 4 lb / ft 3 (32.0kg / m 3 Up to 64.1 kg / m² 3 ), 3.0lb / ft 3 Up to 3.5 lb / ft 3 (48.6kg / m 3 Up to 56.1 kg / m²3 It can have a foam density of ).

[0048] To apply the sealant composition to a surface, the foamed shell is first saturated with the sealant and then applied to the surface using a back-and-forth motion. The shell can be saturated with the curable sealant composition by hand or by extruding the curable sealant composition through a perforation in the foamed shell. A sealant layer having a uniform thickness and being substantially free of defects such as bubbles can be obtained by passing a roller applicator back and forth across a section of the surface at a rate of, for example, 1 to 5 seconds per pass.

[0049] The applicator provided by the present disclosure can be used to apply a viscous curable coating composition, such as a sealant barrier coating composition. The curable coating composition may have a viscosity of, for example, 1,000 cp to 10,000 cp (1 PaX to 10 PaX), 1,500 cp to 8,000 cp (1.5 PaX to 8 PaX), 2,000 cp to 6,000 cp (2 PaX to 6 PaX), or 2,500 cp to 4,000 cp (2.5 PaX to 4 PaX).

[0050] The applicator provided by the present disclosure can be used to apply a curable coating composition having a long pot life. Pot life refers to the time from when the co-reactive component of the composition is first mixed until the time when the curable composition is no longer operable and therefore cannot be applied to the substrate surface.

[0051] While curable coating compositions with short pot life may be used, additional consideration is required regarding the possibility that changes in the viscosity of the composition during the application process may complicate the ability to apply the curable sealant composition through an applicator.

[0052] A curable coating composition having a long pot life may have a pot life of, for example, more than 2 hours, more than 4 hours, more than 6 hours, or more than 8 hours. A curable coating composition having a long pot life may have a pot life of, for example, 2 hours to 12 hours, 2 hours to 12 hours, 2 hours to 10 hours, or 2 hours to 8 hours.

[0053] Examples of curable coating compositions having a long pot life include a cure-on-demand system. A cure-on-demand system refers to a sealant composition comprising a reactant having a slow intrinsic reaction rate and a latent catalyst, or a reactant having a fast intrinsic reaction rate in which at least one of the reactants is latent.

[0054] The reactants and catalysts of a custom curing system can be combined into a single part system and stored, for example, for several weeks or months.

[0055] Custom curing systems include a coating composition having a latent catalyst, a composition curable using chemical radiation such as a UV curing system, a coating composition having a latent reactant or blocked reactant such as a moisture-curable coating composition, and a composition comprising an encapsulated catalyst.

[0056] The curable coating composition may comprise, for example, fillers, catalysts, flow modifiers, reactive diluents, or a combination of any of these. The curable coating composition may comprise, for example, 1 weight% to 90 weight% of fillers or a combination of fillers, wherein the weight% is based on the total weight of the coating composition. The curable coating composition may comprise, for example, 1 volume% to 90 volume% of fillers or a combination of fillers, wherein the volume% is based on the total weight of the coating composition.

[0057] The applicator may include one or more devices for initiating a curing reaction. For example, in the case of a thermal curing system, the nozzle exit may be heated. Alternatively, heat may be applied after the extruded sealant is applied to the surface, for example, by using a radiant heat source or through the absorption of radiation such as infrared.

[0058] In the case of radical curing chemistry, chemical radiation may be applied while and / or after the material is extruded from the applicator slit. Examples of chemical radiation include, for instance -line, - Includes ultraviolet (UV) light including rays, X-rays, UVA, UVA and UVC spectra, visible light, blue light, infrared, near-infrared, or electron beams.

[0059] The applicator provided by the present disclosure may include an integrated curing device or may be used in conjunction with a curing device. The curing device may be a device that initiates a curing reaction of a custom curable sealant composition. The curing device may include an energy source from which energy can initiate a curing reaction. For example, energy may be applied to the curable coating composition while the curable coating composition passes through one or more sections of the applicator, while the curable coating composition passes through a nozzle exit and is applied to a substrate surface, and / or after the curable coating composition is applied to a substrate surface. The energy may include, for example, chemical radiation, thermal energy, acoustic energy, mechanical energy, microwave energy, infrared radiation, or any combination thereof.

[0060] During operation, the applicator is fixed to the surface of the part and guided by hand across the surface. However, a fully automated drawing method is also possible.

[0061] The applicator provided by the present disclosure may be used to apply a coating layer having a thickness of, for example, 0.1 mm to 10 mm, 0.2 mm to 8 mm, 0.3 mm to 6 mm, 0.4 mm to 4 mm, 0.5 mm to 3 mm, or 1 mm to 2 mm. The applicator provided by the present disclosure may be used to apply a coating layer having a thickness of, for example, greater than 0.1 mm, greater than 0.5 mm, greater than 1 mm, greater than 2 mm, greater than 4 mm, or greater than 6 mm. The applicator provided by the present disclosure may be used to apply a coating layer having a thickness of, for example, less than 10 mm, less than 8 mm, less than 6 mm, less than 4 mm, less than 2 mm, or less than 1 mm.

[0062] The extrusion applicator provided by the present disclosure may be configured to provide an extrusion comprising a single composition.

[0063] The extrusion applicator provided by the present disclosure may also be configured to provide co-extrusion. The co-extrusion may include a sealant layer having various compositions.

[0064] Accordingly, the extrusion applicator provided by the present disclosure can be used to apply a single-layer coating, or a multi-layer coating such as a coating having 1 to 4 layers, such as 1 layer, 2 layers, 3 layers, or 4 layers.

[0065] The multilayer coating may include, for example, an adhesive layer, a protective layer, a pigment layer, an electrically conductive layer, and an external aesthetic layer.

[0066] Multiple materials for providing a multilayer coating can be pumped into the inlet, transition section, and / or nozzle section of the applicator. Suitable pumps such as syringe pumps, peristaltic pumps, or progressive cavity pumps may be used.

[0067] Multiple compositions can have different viscosities.

[0068] The multilayer can have different thicknesses. For example, the central layer can provide mechanical and solvent resistance properties; the lower or inner layer can facilitate the adhesion of the multilayer coating to the substrate; and the outer or outer layer can provide desired aesthetic qualities.

[0069] Extrusion applicators can be manufactured using any suitable method, such as additive manufacturing, injection molding, insert molding, metal casting, or other manufacturing methods.

[0070] At least some of the sections or parts of the sections may be made of different materials. For example, the transition section may be made of a high-elasticity material to provide structural strength to the applicator. The nozzle section, or at least the nozzle section adjacent to the exit slit, may comprise a low-modulus material designed to facilitate the nozzle's ability to accommodate non-planar surfaces.

[0071] The applicator provided by the present disclosure can be used to apply sealants such as aerospace sealants. A barrier coating refers to a sealant layer applied over a thicker layer to serve as a secondary solvent-resistant layer. An example of an aerospace barrier coating is disclosed in U.S. Application Publication No. 2019 / 169465 A1. The barrier coating may comprise, for example, a thiol-terminated prepolymer and an alkenyl-terminated urethane-containing prepolymer and / or an alkenyl-terminated urea-containing prepolymer. The barrier coating may be a UV-curable barrier sealant coating.

[0072] The coating composition may be a sealant composition such as an aerospace sealant composition.

[0073] The aerospace sealant composition may include a combination of a sulfur-containing prepolymer or a sulfur-containing polymer.

[0074] The sulfur-containing prepolymer contains one or more thioethers-S n- Refers to a prepolymer having a group, where n can be, for example, 1 to 6 in the backbone of the prepolymer. Prepolymers containing only thiols or other sulfur-containing groups as terminal groups or pendant groups are not included in sulfur-containing prepolymers. The prepolymer backbone refers to the portion of the prepolymer having repeating segments. Thus, HS-RR(-CH2-SH)-[-R-(CH2)2-S(O)2-(CH2)-S(O)2] n A prepolymer having a -CH=CH2 structure is not included in the sulfur-containing prepolymer, where each R is a portion that does not contain a sulfur atom. A prepolymer having a HS-RR(-CH2-SH)-[-R-(CH2)2-S(O)2-(CH2)-S(O)2]-CH=CH2 structure is included in the sulfur-containing prepolymer, where at least one R is a portion containing a sulfur atom, for example, a thioether group.

[0075] Sulfur-containing prepolymers can impart chemical resistance to cured sealants.

[0076] Prepolymer backbones exhibiting chemical resistance may have a high sulfur content. For example, sulfur-containing prepolymer backbones may have a large sulfur content of more than 10 wt%, more than 12 wt%, more than 15 wt%, more than 18 wt%, more than 20 wt%, or more than 25 wt%, where wt% is based on the total weight of the prepolymer backbone. Chemical-resistant prepolymer backbones may have a sulfur content of, for example, 10 wt% to 25 wt%, 12 wt% to 23 wt%, 13 wt% to 20 wt%, or 14 wt% to 18 wt%, where wt% is based on the total weight of the prepolymer backbone.

[0077] The sealant composition may comprise, for example, 40% to 80% by weight, 40% to 75% by weight, 45% to 70% by weight, or 50% to 70% by weight of a sulfur-containing prepolymer or a combination of sulfur-containing prepolymers, wherein the weight% is based on the total weight of the sealant composition. The sealant composition may comprise, for example, more than 40% by weight, more than 50% by weight, more than 60% by weight, more than 70% by weight, more than 80% by weight, or more than 90% by weight of a sulfur-containing prepolymer or a combination of sulfur-containing prepolymers, wherein the weight% is based on the total weight of the sealant composition. The sealant composition may include, for example, less than 90 wt%, less than 80 wt%, less than 70 wt%, less than 60 wt%, less than 50 wt%, or less than 40 wt% of a sulfur-containing prepolymer or a combination of sulfur-containing prepolymers, wherein the weight% is based on the total weight of the sealant composition.

[0078] Examples of prepolymers having a sulfur-containing backbone include polythioether prepolymers, polysulfide prepolymers, sulfur-containing polyformal prepolymers, monosulfide prepolymers, and any combination thereof.

[0079] The prepolymer may include a polythioether prepolymer or a combination of polythioether prepolymers.

[0080] The polythioether prepolymer may include a polythioether prepolymer comprising at least one moiety having the structure of Formula 1, a thiol-terminated polythioether prepolymer of Formula 1a, a terminally modified polythioether of Formula 1b, or a combination of the above:

[0081] -SR 1 -[SASR 1 -] n -S- (1)

[0082] HS-R 1 -[SASR 1 -]n -SH (1a)

[0083] R 3 -SR 1 -[SASR 1 -] n -SR 3 (1b)

[0084] Here,

[0085] n can be an integer from 1 to 60;

[0086] Each R 1 C independently 2-10 Alkandile, C 6-8 Cycloalkanedil, C 6-14 Alkancycloalkanidiyl, C 5-8 Heterocycloalkanedil and -[(CHR) p -X-] q (CHR) r - can be selected from, where,

[0087] p can be an integer between 2 and 6;

[0088] q can be an integer between 1 and 5;

[0089] r can be an integer between 2 and 10;

[0090] Each R can be independently selected from hydrogen and methyl; and

[0091] Each X can be independently selected from O, S, and SS; and

[0092] Each A may independently be a portion derived from a polyvinyl ether of formula (2) or a polyalkenyl polyfunctionalizing agent of formula (3):

[0093] CH2=CH-O-(R 2 -O) m -CH=CH2(2)

[0094] B(-R 4 -CH=CH2) z (3)

[0095] Here,

[0096] m can be an integer from 0 to 50;

[0097] Each R 2 C independently 1-10 Alkandile, C 6-8 Cycloalkanedil, C 6-14 Alkancycloalkanedil, and -[(CHR) p -X-] q (CHR) r - can be selected from, where p, q, r, R and X are R 1 As defined for;

[0098] Each R 3 can be a moiety containing a terminal reaction group independently;

[0099] B is a z-valent polyalkenyl polyfunctionalizing agent B(-R 4 -CH=CH2) z Represents the core of, where

[0100] z can be an integer between 3 and 6; and

[0101] Each R 4 C independently 1-10 Alkandile, C 1-10 Heteroalkanedyl, substituted C 1-10 Alkanedyl and substituted C 1-10 It can be selected from heteroalkanides.

[0102] In the moiety of formula (1) and the prepolymer of formulas (1a)-(1b), each A can be independently selected from the moiety of formula (2a) and the moiety of formula (3a):

[0103] -(CH2)2-O-(R 2 -O) m -(CH2)2- (2a)

[0104] B{-R 4 -(CH2)2-}2{-R 4 -(CH2)2-S-[-R 1 -SASR 1 -] n -SH}z-2 (3a)

[0105] Here, m, R 1 , R 2 , R 4 , A, B, m, n and z are defined as in chemical formula (1), chemical formula (2) or chemical formula (3).

[0106] A method for synthesizing sulfur-containing polythioethers is disclosed, for example, in U.S. Patent No. 6,172,179.

[0107] The backbone of a thiol-terminated polythioether prepolymer can be modified to improve properties such as adhesion, tensile strength, elongation, UV resistance, hardness, and / or flexibility of sealants and coatings prepared using the polythioether prepolymer. For example, adhesion promoters, antioxidants, metal ligands, and / or urethane bonds may be incorporated into the backbone of the polythioether prepolymer to enhance one or more performance properties. Examples of backbone-modified polythioether prepolymers are disclosed, for example, in U.S. Patent No. 8,138,273 (containing urethane), U.S. Patent No. 9,540,540 (containing sulfone), U.S. Patent No. 8,952,124 (containing bis(sulfonyl)alkanol), U.S. Patent No. 9,382,642 (containing metal ligand), U.S. Application Publication No. 2017 / 0114208 (containing antioxidant), PCT International Publication No. WO 2018 / 085650 (containing sulfur-containing divinyl ether), and PCT International Publication No. WO 2018 / 031532 (containing urethane). Polythioether prepolymers include the prepolymers described in U.S. Application Publications No. 2017 / 0369737 and 2016 / 0090507.

[0108] Examples of suitable thiol-terminated polythioether prepolymers are disclosed, for example, in U.S. Patent No. 6,172,179. Thiol-terminated polythioether prepolymers may include Permapol® P3.1E, Permapol® P3.1E-2.8, Permapol® L56086, or any combination of the above, each available from PPG Aerospace. These Permapol® products are included in the thiol-terminated polythioether prepolymers of formulas (2), (2a), and (2b). Thiol-terminated polythioethers include the prepolymers described in U.S. Patent No. 7,390,859 and the urethane-containing polythiols described in U.S. Application Publications No. 2017 / 0369757 and 2016 / 0090507.

[0109] The sulfur-containing prepolymer may include a polysulfide prepolymer or a combination of polysulfide prepolymers.

[0110] Polysulfide prepolymers have one or more polysulfide bonds in the prepolymer backbone, i.e., -S where x is 2 to 4. x - refers to a prepolymer containing bonds. Polysulfide prepolymers may have two or more sulfur-sulfur bonds. Suitable thiol-terminated polysulfide prepolymers are marketed, for example, by AkzoNobel and Toray Industries, Inc. under the trade names Thioplast® and Thiokol-LP®, respectively.

[0111] Examples of suitable polysulfide prepolymers are disclosed, for example, in U.S. Patent Nos. 4,623,711; 6,172,179; 6,509,418; 7,009,032; and 7,879,955.

[0112] Examples of suitable thiol-terminated polysulfide prepolymers include Thioplast® G polysulfides such as Thioplast® G1, Thioplast® G4, Thioplast® G10, Thioplast® G12, Thioplast® G21, Thioplast® G22, Thioplast® G44, Thioplast® G122, and Thioplast® G131, which are commercially available from AkzoNobel. Thioplast® G resin is a liquid thiol-terminated polysulfide prepolymer in which difunctional and trifunctional molecules are mixed, wherein the difunctional thiol-terminated polysulfide prepolymer has the structure of the following chemical formula (4), and the trifunctional thiol-terminated polysulfide polymer may have the structure of the chemical formula (5):

[0113] HS-(-R 5 -SS-) d -R 5 -SH (4)

[0114] HS-(-R 5 -SS-) a -CH2-CH{-CH2-(-SSR 5 -) b -SH}{-(-SSR 5 -) c -SH} (5)

[0115] Here, each R 5 is -(CH2)2-O-CH2-O-(CH2)2- and d = a + b + c, where the value of d can be 7 to 38 depending on the amount of trifunctional crosslinking agent (1,2,3-trichloropropane; TCP) used during the synthesis of the polysulfide prepolymer. Thioplast® G polysulfide may have a number average molecular weight of less than 1,000 Da to 6,500 Da, an SH content of 1% to 5.5% or more, and a crosslinking density of 0% to 2.0%.

[0116] The polysulfide prepolymer may further include a terminally modified polysulfide prepolymer having the structure of formula (4a), a terminally modified polysulfide prepolymer having the structure of formula (5a), or a combination thereof:

[0117] R 3 -S-(-R 5 -SS-) d -RSR 3 (4a)

[0118] R 3 -S-(-R 5 -SS-) a -CH2-CH{-CH2-(-SSR 5 -) b -S-}{-(-SSR 5 -) c -SR 3} (5a)

[0119] Here, d, a, b, c and R5 are defined as in chemical formulas (4) and (5), and R 3 is a part containing a terminal reactive group.

[0120] Examples of suitable thiol-terminated polysulfide prepolymers are also Thiokol® LP2, Thiokol® LP3, Thiokol TM It includes Thiokol® LP polysulfides available from Toray Industries, Inc., such as LP12, Thiokol® LP23, Thiokol® LP33, and Thiokol® LP55. Thiokol® LP polysulfides have a number average molecular weight of 1,000 Da to 7,500 Da, an -SH content of 0.8% to 7.7%, and a crosslinking density of 0% to 2%. Thiokol TM The LP polysulfide prepolymer has the structure of formula (6), and the terminally modified polysulfide prepolymer may have the structure of formula (6a):

[0121] HS-[(CH2)2-O-CH2-O-(CH2)2-SS-] e-(CH2)2-O-CH2-O-(CH2)2-SH (6)

[0122] R 3 -S-[(CH2)2-O-CH2-O-(CH2)2-SS-] e -(CH2)2-O-CH2-O-(CH2)2-SR 3 (6a)

[0123] Here, e can be an integer with a number average molecular weight of 1,000 Da to 7,500 Da, for example, 8 to 80, and each R3 is a portion containing a terminal reactive functional group.

[0124] The thiol-terminated sulfur-containing prepolymer may include Thiokol-LP® polysulfide, Thioplast® G polysulfide, or a combination thereof.

[0125] Examples of thiol-terminated polysulfide prepolymers of chemical formulas (6a) and (6b) are disclosed, for example, in U.S. Application Publication No. 2016 / 0152775, U.S. Patent No. 9,079,833 and U.S. Patent No. 9,663,619.

[0126] The polysulfide prepolymer may include a polysulfide prepolymer having a moiety of formula (7), a thiol-terminated polysulfide prepolymer of formula (7a), a terminal-modified polysulfide prepolymer of formula (7b), or a combination of the above:

[0127] -(R 6 -O-CH2-OR 6 -S m -) n-1 -R 6 -O-CH2-OR 6 - (7)

[0128] HS-(R 6 -O-CH2-OR 6 -S m -) n-1 -R 6 -O-CH2-OR 6 -SH (7a)

[0129] R3 -S-(R 6 -O-CH2-OR 6 -S m -) n-1 -R 6 -O-CH2-ORSR 3 (7b)

[0130] R 6 C 2-4 It is an alkanedile, where m is an integer from 1 to 8 and n is an integer from 2 to 370; and each R 3 is a portion that independently contains a terminal reactive functional group.

[0131] Polysulfide prepolymers of formula (7) and formulas (7a)-(7b) are disclosed, for example, in JP 62-53354.

[0132] Sulfur-containing prepolymers may include sulfur-containing polymorphic prepolymers or combinations of sulfur-containing polymorphic prepolymers. Sulfur-containing polymorphic prepolymers useful for sealant applications are disclosed, for example, in U.S. Patent No. 8,729,216 and U.S. Patent No. 8,541,513.

[0133] The sulfur-containing polymorphic prepolymer may include a moiety of the following formula (8), a thiol-terminated sulfur-containing polymorphic prepolymer of formula (8a), a terminally modified sulfur-containing polymorphic prepolymer of formula 8b, a thiol-terminated sulfur-containing polymorphic prepolymer of formula (8c), a terminally modified sulfur-containing polymorphic prepolymer of formula (8d), or a combination of the foregoing:

[0134] R 8 -(S) v -R 8 -[OC(R 2 )2-OR 8 -(S) v -R 1 -] n - (8)

[0135] R 10 -R 8 -(S) v-R 8 -[OC(R 9 )2-OR 8 -(S) v -R 8 -] h -R 10 (8a)

[0136] R 3 -R 8 -(S) v -R 8 -[OC(R 9 )2-OR 8 -(S) v -R 8 -] h -R 3 (8b)

[0137] {R 10 -R 8 -(S) v -R 8 -[OC(R 9 )2-OR 8 -(S) v -R 8 -] h -OC(R 9 )2-O-} m Z (8c)

[0138] {R 3 -R 8 -(S) v -R 8 -[OC(R 9 )2-OR 8 -(S) v -R 8 -] h -OC(R 9 )2-O-} m Z (8d)

[0139] Here, h can be an integer from 1 to 50; each v can be independently selected from 1 and 2; and each R 8 C 2-6 It can be an alkandiyl; and each R 9 is independently hydrogen, C 1-6 Alkyl, C 7-12 Phenylalkyl, substituted C 7-12 Phenylalkyl, C 6-12Cycloalkylalkyl, substituted C 6-12 Cycloalkylalkyl, C 3-12 Cycloalkyl, substituted C 3-12 Cycloalkyl, C 6-12 Aryl and substituted C 6-12 Can be selected from among aryls; each R 10 is a portion containing a terminal thiol group; and each R 3 is a portion containing a terminal reactive functional group other than a thiol group independently; and Z is m is the parent polyol Z(OH) m It can be derived from the core of.

[0140] The sulfur-containing prepolymer may include a monosulfide prepolymer or a combination of monosulfide prepolymers.

[0141] The monosulfide prepolymer may include a moiety of formula (9), a thiol-terminated monosulfide prepolymer of formula (9a), a thiol-terminated monosulfide prepolymer of formula (9b), a terminally modified monosulfide prepolymer of formula 9c, a terminally modified monosulfide prepolymer of formula (9d), or a combination of the foregoing:

[0142] -SR 13 -[-S-(R 11 -X) w -(R 12 -X) u -R 13 -] x -S- (9)

[0143] HS-R 13 -[-S-(R 11 -X) w -(R 12 -X) u -R 13 -] x -SH (9a)

[0144] {HS-R 13 -[-S-(R 11 -X) w -(R 12 -X) u -R 13 -] x-S-V'-} z B (9b)

[0145] R 3 -SR 13 -[-S-(R 11 -X) w -(R 12 -X) u -R 13 -] x -SR 3 (9c)

[0146] {R 3 -SR 13 -[-S-(R 11 -X) u -(R 12 -X) q -R 13 -] x -S-V'-} z B (9d)

[0147] Here,

[0148] Each R 11 C independently 2-10 Alkanedile, for example, C 2-6 Alkandiyl; C 2-10 Branched alkanedils, e.g., C 3-6 C having one or more pendant groups that may be branched alkanidiyls or alkyl groups, such as methyl or ethyl groups, for example. 3-6 Branched alkanedil; C 6-8 Cycloalkanedil; C 6-10 C such as alkylcycloalkanedils 6-14 Alkylcycloalkanediyl; and C 8-10 It can be selected from alkylarendiyls;

[0149] Each R 12 is independently hydrogen, C 1-10 n-alkanedyl, e.g., C 1-6 n-alkanedyl, C having one or more pendant groups which may be alkyl groups such as methyl or ethyl groups, for example 3-6 C such as branched alkanedils 2-10 Branched alkanedil; C 6-8 Cycloalkanedil; C6-10 C such as alkylcycloalkanedils 6-14 Alkylcycloalkanediyl; and C 8-10 It can be selected from alkylarendiyls;

[0150] Each R 13 is independently hydrogen, C 1-10 n-alkanedyl, e.g., C 1-6 n-alkanedyl, C having one or more pendant groups which may be alkyl groups such as methyl or ethyl groups, for example 3-6 C such as branched alkanedils 2-10 Branched alkanedil; C 6-8 Cycloalkanidiyl; C 6-10 C of alkylcycloalkanedils, etc. 6-14 Alkylcycloalkanediyl; and C 8-10 It can be selected from alkylarendiyls;

[0151] Each X can be selected independently from O and S;

[0152] w can be an integer from 1 to 5;

[0153] u can be 0 to 5 integers; and

[0154] x can be an integer between 1 and 60, such as 2 to 60, 3 to 60, or 25 to 35;

[0155] Each R 3 is independently selected from reactive functional groups;

[0156] B is z is a polyfunctionalizing agent B(-V) z Represents the core of, where:

[0157] z can be an integer between 3 and 6; and

[0158] Each V may be a portion containing a terminal group that reacts with a thiol group;

[0159] Each -V'- can be derived from the reaction of -V and thiol.

[0160] A method for synthesizing a thiol-terminated monosulfide comprising a moiety of formula (10) or a prepolymer of formulas (9b)-(9c) is disclosed, for example, in U.S. Patent No. 7,875,666.

[0161] The monosulfide prepolymer may include a thiol-terminated monosulfide prepolymer comprising a moiety of formula (10), a moiety of formula (10a), a thiol-terminated monosulfide prepolymer of formula (10b), a thiol-terminated monosulfide prepolymer of formula (10c), a thiol-terminated monosulfide prepolymer of formula (10d), or a combination of the foregoing:

[0162] -[-S-(R 14 -X) w -C(R 15 )2-(XR 14 ) u -] x -S- (10)

[0163] H-[-S-(R 14 -X) w -C(R 15 )2-(XR 14 ) u -] x -SH (10a)

[0164] R 3 -[-S-(R 14 -X) w -C(R 15 )2-(XR 14 ) u -] x -SR 3 (10b)

[0165] {H-[-S-(R 14 -X) w -C(R 15 )2-(XR 14 ) u -] x -S-V'-} z B (10c)

[0166] {R 3 -[-S-(R 14 -X) w -C(R15 )2-(XR 14 ) u -] x -S-V'-} z B (10d)

[0167] Here,

[0168] Each R 14 C independently 2-10 Alkanedile, for example, C 2-6 Alkandiyl; C 3-10 Branched alkanedils, e.g., C 3-6 C having one or more pendant groups that may be a branched alkanidiyl or an alkyl group such as, for example, a methyl or ethyl group 3-6 Branched alkanedil; C 6-8 Cycloalkanedil; C 6-10 C such as alkylcycloalkanedils 6-14 Alkylcycloalkanediyl; and C 8-10 It can be selected from alkylarendiyls;

[0169] Each R 15 is independently hydrogen, C 1-10 n-alkanedyl, e.g., C 1-6 n-alkanedyl, C having one or more pendant groups which may be alkyl groups such as methyl or ethyl groups. 3-6 C such as branched alkanedils 3-10 Branched alkanedil; C 6-8 Cycloalkanidiyl; C 6-10 C such as alkylcycloalkanedils 6-14 Alkylcycloalkanediyl; and C 8-10 It can be selected from alkylarendiyls;

[0170] Each X can be selected independently from O and S;

[0171] w can be an integer from 1 to 5;

[0172] u can be an integer from 1 to 5;

[0173] x can be an integer between 1 and 60, such as 2 to 60, 3 to 60, or 25 to 35;

[0174] Each R 6 is the portion containing a terminal functional group;

[0175] B is z is a polyfunctionalizing agent B(-V) z Represents the core of, where:

[0176] z can be an integer between 3 and 6; and

[0177] Each V may be a portion containing a terminal group that reacts with a thiol group;

[0178] Each -V'- can be derived from the reaction of -V and thiol.

[0179] A method for synthesizing monosulfides of chemical formulas (10)-(10d) is disclosed, for example, in U.S. Patent No. 8,466,220.

[0180] Examples of other chemically resistant prepolymers include polytetrafluoroethylene, polyvinylidene difluoride, polyethylenetetrafluoroethylene, fluoroethylene propylene, perfluoroalkoxy, ethylene chlorotrifluoroethylene, polychlorotrifluoroethylene, fluoroethylene propylene polymer, polyamide, polyethylene, polypropylene, ethylene-propylene, fluorinated ethylene-propylene, polysulfone, polyarylethersulfone, polyethersulfone, polyimide, polyethylene terephthalate, polyetherketone, polyetheretherketone, polyetherimide, polyphenylene sulfide, polyarylsulfone, polybenzimidazole, polyamideimide, liquid crystal polymer, or combinations of the foregoing.

[0181] The applicator provided by the present disclosure can be used to apply sealants, such as aerospace sealants. A sealant composition means a composition capable of producing a cured material having the ability to resist atmospheric conditions such as moisture and temperature and to block, at least partially, the permeation of materials such as water, fuel, and other liquids and gases.

[0182] The aerospace seals provided by the present disclosure may be formulated as Class A, Class B, or Class C seals. Class A seals refer to brushable seals having a viscosity of 1 to 500 poise (0.1 Pa-sec to 50 Pa-sec) and are designed for brush application. Class B seals refer to extrudable seals having a viscosity of 4,500 to 20,000 poise (450 Pa-sec to 2,000 Pa-sec) and are designed for extrusion application via a pneumatic gun. Class B seals may be used to form fillets and seals on vertical surfaces or edges where low slump / slag is required. Class C seals have a viscosity of 500 to 4,500 poise (50 Pa-sec to 450 Pa-sec) and are designed for application with a roller or a comb-tooth spreader. Class C seals may be used for surface sealing. Viscosity can be measured according to Section 5.3 of the SAE Aerospace Standard AS5127 / 1C published by the SAE International Group.

[0183] Aerospace sealants may exhibit properties acceptable for use in aerospace sealant applications. Generally, sealants used in the aerospace and aviation fields are desirable to exhibit the following properties: peel strength exceeding 20 pounds per linear inch (pli) on an Aerospace Material Specification (AMS) 3265B substrate measured under dry conditions after immersion in JRF Type I for 7 days and immersion in a 3% NaCl solution according to the AMS 3265B test specification; tensile strength between 300 pounds per square inch (psi) and 400 psi; tear strength exceeding 50 pounds per linear inch (pli); elongation between 250% and 300%; and hardness greater than 40 Durometer A. These and other cured sealant properties suitable for the aerospace and aviation fields are disclosed in AMS 3265B. Additionally, the compositions provided by the present disclosure for use in aviation and aircraft applications when cured preferably exhibit a volume expansion rate of 25% or less after immersion in JRF (Jet Reference Fluid) Type 1 at 60°C (140°F) and 760 torr (101 kPa) for one week. Other properties, ranges, and / or thresholds may be suitable for other sealant applications.

[0184] The chemical resistance of a sealant may be associated with cleaning solvents, fuels, hydraulic fluids, lubricants, oils, and / or salt sprays. Chemical resistance refers to the ability of a part to maintain acceptable physical and mechanical properties after exposure to atmospheric conditions such as moisture and temperature, and after exposure to chemicals such as cleaning solvents, fuels, hydraulic fluids, lubricants, and / or oils. Generally, chemically resistant sealants may exhibit a % expansion of less than 25%, less than 20%, less than 15%, or less than 10% after immersion in chemicals at 70°C for 7 days, where % expansion is determined according to EN ISO 10563.

[0185] Sealants useful in the aerospace field may possess fuel resistance. In relation to aerospace sealant applications, fuel resistance means that when the composition is applied to a substrate and cured, it can provide a cured product, such as a sealant, that exhibits a volume expansion of 40% or less—25% or less in some cases, 20% or less in others, and 10% or less in others—after immersion for one week at 140°F (60°C) and 760 torr (101 kPa) in JRF Type I according to methods similar to those described in ASTM D792 (American Society for Testing and Materials) or AMS 3269 (Aerospace Material Specification). JRF Type I used for fuel resistance measurements has the following composition: Toluene: 28 ± 1 vol%; Cyclohexane (technical): 34 ± 1 vol%; Isooctane: 38 ± 1 vol%; and tertiary dibutyl disulfide: 1 ± 0.005 volume% (see AMS 2629, § 3.1.1., July 1, 1989, available from the Society of Automotive Engineers (SAE)).

[0186] After exposure to a jet reference fluid (JRF type 1) at 60°C for 168 hours according to ISO 1817, the cured sealant may exhibit a tensile strength greater than 1.4 MPa determined according to ISO 37, a tensile elongation greater than 150% determined according to ISO 37, and a hardness greater than Shore 30A determined according to ISO 868, and the test is performed at a temperature of 23°C and a humidity of 55% RH.

[0187] After exposure to de-icing fluid according to ISO 11075 Type 1 for 168 hours at 60°C, the cured sealant may exhibit a tensile strength greater than 1 MPa determined according to ISO 37 and a tensile elongation greater than 150% determined according to ISO 37, and the test is performed at a temperature of 23°C and a humidity of 55% RH.

[0188] After exposure to phosphate ester hydraulic fluid (Skydrol® LD-4) for 1,000 hours at 70°C, the cured sealant may exhibit a tensile strength greater than 1 MPa as determined according to ISO 37, a tensile elongation greater than 150% as determined according to ISO 37, and a hardness greater than Shore 30A as determined according to ISO 868, and the test is performed at a temperature of 23°C and a humidity of 55% RH. The chemical-resistant composition may exhibit a % expansion of less than 25%, less than 20%, less than 15%, or less than 10% after immersion in chemicals at 70°C for 7 days, and the % expansion is determined according to EN ISO 10563.

[0189] The cured coating may exhibit a hardness greater than Shore 20A, Shore 30A, Shore 40A, Shore 50A, or Shore 60A, for example, where the hardness is determined according to ISO 868 at 23°C / 55%RH.

[0190] The cured coating may exhibit a tensile elongation of at least 200% and a tensile strength of at least 200 psi when measured according to the procedure described in AMS 3279, § 3.3.17.1 and test procedure AS5127 / 1, § 7.7.

[0191] The cured coating may exhibit an overlapping shear strength greater than 200 psi (1.38 MPa) when measured according to the procedure described in paragraph 7.8 of SAE AS5127 / 1, for example, at least 220 psi (1.52 MPa), at least 250 psi (1.72 MPa), and in some cases at least 400 psi (2.76 MPa).

[0192] The cured coating may meet or exceed the requirements for aerospace sealants specified in AMS 3277.

[0193] Aerospace sealants are thermosetting compositions containing two or more co-reactive components. Various curing chemicals such as thiol / alkenyl, thiol / epoxy, thiol / Michael receptor, isocyanate / hydroxyl, and isocyanate / amine may be used.

[0194] The applicator provided by the present disclosure can be used to apply a coating of a viscous composition having a cured thickness, for example, 5 mils to 40 mils (127 μm to 508 μm), for example, 5 mils to 35 mils, 5 mils to 30 mils, or 10 mils to 30.

[0195] The applicator provided by the present disclosure may be used to apply coating compositions, such as sealant compositions, having a viscosity of, for example, 100 cp to 10,000 cp or 500 cp to 5,000 cp, as measured at a speed of 300 rpm and a temperature of 25°C using a Brookfield CAP 2000 viscometer equipped with a No. 6 spindle. The applicator provided by the present disclosure may be used to apply coating compositions, such as sealant compositions, having a viscosity of, for example, greater than 100 cp, greater than 500 cp, greater than 1,000 cp, greater than 2,500 cp, greater than 5,000 cp, greater than 7,500 cp, or greater than 10,000 cp, as measured at a speed of 300 rpm and a temperature of 25°C using a Brookfield CAP 2000 viscometer equipped with a No. 6 spindle.

[0196] The applicator provided by the present disclosure may be used to apply a solvent-free coating composition, for example, a composition having less than 5 weight% of solvent, less than 2 weight% of solvent, less than 1 weight% of solvent, or less than 0.1 weight% of solvent, wherein the weight% is based on the total weight of the composition.

[0197] The applicator provided by the present disclosure can also be used to apply a two-part sealant system.

[0198] In a two-part system, two reactive components begin to react when combined. For example, the first part of the two-part system may comprise a polythiol, and the second part may comprise a compound reactive to the polythiol, such as a polyalkenyl, polyepoxide, polyisocyanate, polyfunctional Michael receptor, or polythiol. One or both parts may additionally comprise a catalyst.

[0199] For use with an applicator provided by the present disclosure, the first and second portions may be combined and mixed before being pumped into the applicator and / or may be combined and mixed using a mixer located immediately before the applicator inlet. Examples of suitable mixers include static mixers and dynamic mixers.

[0200] Aerospace sealants are designed to maintain mechanical properties even after exposure to solvents such as fuel and hydraulic fluid. Solvent-resistant sealants may contain prepolymers with a sulfur content of, for example, greater than 5 wt%, greater than 10 wt%, or greater than 15 wt%, wherein the weight% is based on the weight% of the prepolymer. Examples of suitable sulfur-containing prepolymers include polythioethers, polysulfides, monosulfides, and sulfur-containing polyformals.

[0201] One of the purposes of applying a coating using extrusion or roller coating is to prevent air from being incorporated into the curable composition during application, as may occur during spray coating. Before applying the coating composition using the applicator provided by the present disclosure, the coating composition may be degassed under vacuum to remove any incorporated air. All supply connections and the applicator housing may be sealed to prevent air from being incorporated into the coating composition during application.

[0202] The applicator provided by the present disclosure may be used to apply a coating onto any suitable substrate. For example, the substrate may be an untreated or treated metal or metal alloy substrate, such as aluminum, aluminum alloy, steel, or steel alloy substrate. The substrate may be a polymer substrate, such as a thermoplastic polymer substrate or a thermosetting polymer substrate. The coating may be applied over a base layer, such as a primer coating or a sealant layer.

[0203] The applicator provided by the present disclosure can be used to apply a coating to any suitable part. Examples of suitable parts include automotive parts, architectural parts, construction parts, electronic parts, furniture, medical devices, portable devices, communication devices, exercise equipment, clothing, toys, etc.

[0204] Parts such as automotive parts include automotive parts and aerospace automotive parts.

[0205] The applicator provided by the present disclosure can be used to coat the interior and exterior parts of vehicles, such as automotive parts, rail vehicle parts, aerospace vehicle parts, military vehicle parts, and ship parts.

[0206] Car parts can be new parts or replacement parts.

[0207] The term "vehicle" is used in its broadest sense and includes all types of aircraft, spacecraft, ships, and ground vehicles. For example, vehicles include aircraft, such as private aircraft, small, medium, and large commercial passenger aircraft, cargo planes, and military aircraft; helicopters, such as private, commercial, and military helicopters; aerospace vehicles, including rockets, and other spacecraft. Vehicles may include ground vehicles, such as trailers, automobiles, trucks, buses, vans, construction vehicles, golf carts, motorcycles, bicycles, scooters, trains, and railway vehicles. Vehicles may also include vessels, such as ships, boats, and hovercrafts.

[0208] Vehicle parts may be, for example, automotive parts including automobiles, trucks, buses, vans, motorcycles, scooters, and recreational vehicles; railway vehicles including trains and trams; bicycles; aerospace vehicles including airplanes, rockets, spacecraft, jets, and helicopters; military vehicles including jeeps, transport vehicles, combat support vehicles, troop carriers, infantry fighting vehicles, mine-resistant vehicles, light armored vehicles, small utility vehicles, and military trucks; and vessels including ships, boats, and recreational vessels.

[0209] Examples of aircraft vehicles include the F / A-18 jet or related aircraft such as the F / A-18E Super Hornet and F / A-18F; Boeing 787 Dreamliner, 737, 747, 717 passenger aircraft and related aircraft (produced by Boeing Commercial Airplanes); V-22 Osprey; VH-92, S-92 and related aircraft (produced by NAVAIR and Sikorsky); G650, G600, G550, G500, G450 and related aircraft (produced by Gulfstream); and A350, A320, A330 and related aircraft (produced by Airbus). The methods provided by the present disclosure include those produced by Bombardier Aerospace, such as Bombardier Inc. and / or the Canadair Regional Jet (CRJ) and related aircraft; and those produced by Lockheed Martin, such as the F-22 Raptor, F-35 Lightning and related aircraft. It may be used in any suitable commercial, military, or general aviation aircraft, such as those produced by Northrop Grumman, including the B-2 Spirit and related aircraft; those produced by Pilatus Aircraft Ltd.; those produced by Eclipse Aviation Corporation; or those produced by Eclipse Aerospace (Kestrel Aircraft).

[0210] Vehicle parts can be internal or external parts of the vehicle.

[0211] The vehicle may include an automobile, and the automobile parts may include a hood, doors, side panels, bumpers, roof, wheel wells, dashboard, seats, trunk, handle, floor, chassis, cabin, chassis, cargo compartment, steering wheel, fuel tank, engine block, trim, bumpers, and / or battery case.

[0212] The vehicle may include a rail vehicle, and the rail vehicle parts may include an engine and / or a railway vehicle.

[0213] The vehicle may include an aerospace vehicle, and the aerospace components may include a cockpit, fuselage, wings, ailerons, tail, doors, seats, interior panels, fuel tanks, interior panels, flooring, and / or a frame.

[0214] The vehicle may include a military vehicle, and the military vehicle parts may include a hood, doors, side panels, bumpers, roof, wheelhouses, dashboard, seats, trunk, handle, floor, chassis, cabin, chassis, cargo compartment, steering wheel, fuel tank, engine block, trim, bumpers, mounts, turret, chassis and / or battery case.

[0215] The vehicle may include a vessel, and the vessel parts may include a hull, engine mount, seat, handle, chassis, battery, battery mount, fuel tank, interior accessories, flooring and / or panels.

[0216] Automotive parts coated using the primer-surfacer composition provided by the present disclosure may have properties suitable for intended purposes. For example, automotive parts may be designed to be lightweight. Military vehicle exterior parts may be designed to have high impact strength.

[0217] Components for commercial aerospace vehicles can be designed to be lightweight and / or have electrostatic dissipation capabilities. External components for military aircraft can be designed to exhibit RFI / EMI shielding characteristics.

[0218] The applicator provided by the present disclosure can be used to rapidly and cost-effectively coat custom-designed automotive parts, replacement parts, upgrade parts, special parts and / or high-performance parts during small-batch production.

[0219] The parts may include elastomeric articles, for example, seals, sealants, grommets, gaskets, washers, bushings, flanges, insulation, clothing, shoe soles, boots, shoes, handles, bumpers, shock absorbers, mats, tires, supports, automotive parts, aerospace parts, marine parts, sports equipment, toys, novel items, and cases.

[0220] An aspect of the present invention includes a part comprising a coating applied using an applicator provided by the present disclosure.

[0221] example

[0222] The embodiments provided by the present disclosure are further illustrated with reference to the following embodiments describing the methods provided by the present disclosure. It will be apparent to those skilled in the art that many variations of both materials and methods can be practiced without departing from the scope of the present disclosure.

[0223] Example 1

[0224] Application of sealant barrier coating

[0225] A sealant composition useful as an aerospace barrier coating was prepared as described in U.S. Application No. 2019 / 0169465 A1. A barrier coating refers to a sealant layer applied over a thicker layer to serve as a secondary solvent-resistant layer. The sealant composition contained a urethane-containing polythiol prepolymer, a urethane-containing polyalkenyl prepolymer, and optionally a hydroxyl-functional polythiol. The composition containing a UV photoinitiator is UV-curable. The composition also contained an inorganic filler.

[0226] The coating composition was fed into an extrusion applicator at a pressure of approximately 30 psi and applied to an aluminum panel with a nominal wet thickness of 20 mils (508 μm). The formulation had a viscosity of approximately 3,000 cp (3 kPa χs) when measured at a speed of 300 rpm and a temperature of 25°C using a Brookfield CAP 2000 viscometer equipped with a No. 6 spindle.

[0227] The coating composition was also applied to the aluminum panel using a roller. The material was fed into the roller's core. The core had a knap thickness of 0.125 inches or 0.250 inches (3.175 mm to 6.5 mm) and 3.3 lb / ft 3 Up to 3.5 lb / ft 3 (48.6kg / m 3 Up to 56.1 kg / m² 3 It was covered with a polyester polyurethane foam outer shell having a foam density of ). The foam roller was first saturated with a sealant and then applied to an aluminum substrate while moving back and forth for 1 second per pass until the desired thickness was reached and trapped bubbles were no longer visible to the naked eye.

[0228] In addition, a coating composition was applied to an aluminum panel using a draw-down bar. A portion of the coating composition was placed on the aluminum panel between two spacers. The drawn-down bar was secured against the spacers, and as the bar was pulled along the spacers, the coating composition spread out, providing a layer of uniform thickness without air entrapment. The coating applied using the draw-down bar was considered a high-quality coating.

[0229] The applied coating was cured by exposing it to UV radiation. For example, typical curing conditions involved exposing the applied coating to a 4W UV LED lamp using 395nm radiation from a height of about 18cm above the surface for 30 to 60 seconds.

[0230] The thickness of the cured coating was 15 mils (381 μm).

[0231] The cured coating surface was smooth and free of bubbles, as determined by visual inspection.

[0232] The tensile strength and % elongation of the cured coating were determined according to ASTM D412A for samples maintained under ambient conditions (25°C, 50%RH) and exposed to 250°F (121°C) for 24 hours.

[0233]

[0234] Finally, it should be noted that there are alternative methods for implementing the embodiments disclosed herein. Accordingly, the embodiments are to be regarded as exemplary and not restrictive. Furthermore, the claims are not limited to the details provided herein and are entitled to the full scope and equivalents thereof.

Claims

Claim 1 An extrusion applicator comprising: (a) an adapter section including a proximal end, a distal end, and an adapter channel; (b) a transition section mechanically coupled to the adapter section and including a proximal end and a distal end, wherein the transition section defines an internal transition channel including a width and a height; wherein the width of the transition channel increases from a transition inlet to a transition outlet; and wherein the height of the transition channel decreases from a transition inlet to a transition outlet; and (c) a nozzle section mechanically coupled to the transition section, wherein the nozzle section includes a flow control section coupled to the transition section and including a plurality of parallel channels; a pressure control section coupled to the flow control section and including a channel and one or more support structures; and a nozzle section coupled to the pressure control section and including a nozzle outlet having a rectangular slit shape. Claim 2 In claim 1, the flow control section comprises a plurality of parallel channels, an extrusion applicator. Claim 3 An extrusion applicator according to claim 1, wherein the nozzle outlet is characterized by height and width, and the height is adjustable, the width is adjustable, or both the height and the width are adjustable. Claim 4 An extrusion applicator according to claim 1, wherein the adapter channel, the switching channel, the channel of the pressure control section, or any combination of the above comprises a wall having a shear-thinning coating. Claim 5 An extrusion applicator according to claim 1, wherein at least a portion of the nozzle section is configured to conform to the substrate surface when in contact with the substrate surface. Claim 6 The extrusion applicator of claim 1, wherein the extrusion applicator further comprises a curing apparatus, and the curing apparatus comprises an energy source configured to initiate a curing reaction, and the energy comprises chemical radiation, thermal energy, acoustic energy, mechanical energy, microwave energy, infrared radiation, or any combination thereof. Claim 7 delete Claim 8 In claim 1, the extrusion applicator is configured to apply a multilayer coating. Claim 9 A system comprising the extrusion applicator of claim 1. Claim 10 A method for coating a substrate surface, comprising the steps of: pumping a curable coating composition into the adapter section of the extrusion applicator of claim 1; positioning the nozzle outlet adjacent to the surface; and moving the nozzle outlet across the surface to apply the curable coating to the surface. Claim 11 In claim 10, the method wherein the curable coating composition comprises a potential catalyst, a potential reactant, a free radical generator, a water-activating catalyst, or a water-activating reactant. Claim 12 In claim 10, the curable coating composition is characterized by a viscosity of 1,000 cp to 10,000 cp, wherein the viscosity is measured using a Brookfield CAP 2000 viscometer equipped with a No. 6 spindle at a speed of 300 rpm and a temperature of 25°C. Claim 13 A method according to claim 10, further comprising the step of applying energy to the curable coating composition. Claim 14 A coating applied to the surface of a substrate using the method of claim 10. Claim 15 A method for applying a coating, comprising the step of saturating a foam cover of a roller with a curable coating composition, wherein the roller comprises a cylindrical core and a foam cover surrounding the core; the step of repeatedly rolling the saturated foam cover over a substrate surface to apply a layer of the curable coating composition to a substrate surface; and the step of curing the applied curable coating composition to provide a cured coating, wherein the curable coating composition is characterized by a viscosity of 1,000 cp to 10,000 cp, wherein the viscosity is measured at a speed of 300 rpm and a temperature of 25°C using a Brookfield CAP 2000 viscometer equipped with a No. 6 spindle. Claim 16 In paragraph 15, the method wherein the foam cover has a nap thickness of 0.1 inch (2.54 mm) to 0.50 inch (12.7 mm). Claim 17 In paragraph 15, the foam cover is 1.5 lb / ft 3 Up to 5 lb / ft 3 (24.1kg / m 3 Up to 80.1 kg / m² 3 A method having a foam density of ). Claim 18 In claim 15, the method wherein the curable composition has a viscosity of 1,000 cp to 10,000 cp (1 Pa-s to 10 Pa-s). Claim 19 A method according to claim 15, wherein the curing step comprises applying energy to the curable coating composition. Claim 20 A coating applied to the surface of a substrate using the method of claim 15. 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