WO2017048980A1

WO2017048980A1 - Kits and related methods for efficient use of multi-component resin systems

Info

Publication number: WO2017048980A1
Application number: PCT/US2016/051974
Authority: WO
Inventors: James Mcguire, Jr.; Andrew Strange
Original assignee: entrochem Inc
Current assignee: entrochem Inc
Priority date: 2015-09-15
Filing date: 2016-09-15
Publication date: 2017-03-23
Anticipated expiration: 2018-03-15

Abstract

A kit for forming a ready-to-use multi-component resin system comprises: a mixing vessel; a first resin system component contained within the mixing vessel; a second resin system component packaged in proportion for mixing with the first resin system component to form the multi-component resin system; a planetary mixer in which contents of the mixing vessel can be mixed; and at least one dispensing tool for the multi-component resin system. Methods of using the kit comprise sequential steps of: adding the second resin system component to the mixing vessel; mixing contents of the mixing vessel using the planetary mixer to form the multi-component resin system; and filling the dispensing tool with the multi-component resin system of the mixing vessel.

Description

TITLE OF THE INVENTION

[0001] Kits and Related Methods for Efficient Use of Multi-Component Resin Systems

FIELD OF THE INVENTION

[0002] The present invention is directed toward kits and methods for efficient use of multi-component resin systems.

BACKGROUND OF THE INVENTION

[0003] A wide variety of resin systems, including thermosetting resin systems, are known. Single-component resin systems generally remain in their uncured state until they are exposed to an external energy source {e.g., thermal or ultraviolet radiation) that initiates cure of the system. In contrast, once components of a multi-component resin system are mixed, their ability to be efficiently, or even capably, used in an application is time-sensitive. Generally, the viscosity of a mixed resin system increases with time when working with thermosetting resin systems, such as epoxy systems. To quantify the time- sensitivity of a mixed resin system, pot life, working life, and gel time are often used.

[0004] "Pot life" is defined as the amount of time it takes for an initial mixed viscosity to double, or quadruple for lower viscosity products (<1000 cPs).

Timing starts from the moment the product is mixed, and is measured at room temperature (23^°C).

[0005] "Working life," on the other hand, is the amount of time a mixed resin system remains low enough in viscosity that it can still be easily applied to a part or substrate in a particular application. For that reason, working life can vary from application to application, and even by the application method of the resin, so there is generally no uniform method for quantifying this property.

[0006] "Gel time" is another term that is often used interchangeably with pot life, although there are some differences. Both terms are used to describe the thickening of a resin system after it is mixed, but gel time is often tested at elevated temperatures as well. Gel time is determined by heating the resin and observing when it starts to become stringy, or gel-like, though not quite fully cured. It will most likely be at a higher viscosity toward the end of the pot life measurement. This value can be useful, for example, in manufacturing purposes if one needs to move a part before the cure is complete, but does not want any shift in a component placement. It is not, however, associated with a standard quality control test, but is generally determined experimentally in a particular application, if needed.

[0007] Once mixed, resin systems are often dispensed onto a substrate using a syringe- or other relatively fine dimension dispensing tool so as to more accurately and efficiently apply the resin in a particular application. As such, ease of dispensing the resin generally decreases as viscosity of the resin increases after its mixing. If not dispensed rapidly enough after mixing, the resin may cure to such an extent that is no longer capable of being dispensed as intended.

[0008] In order to address this issue, various mixing and dispensing systems have been developed. Certain systems rely on use of cartridges with handheld dispensers, for example, while others rely on meter, mix, and dispense (MMD) equipment. Various factors influence which type of equipment is best- suited for an application. For example, dual cartridge on-demand mixing and dispensing systems for two-component reactive resin systems are known. Dual cartridges, which are also sometimes referred to as compartments, isolate the two resin components until needed. That is, individual components are typically provided within separate compartments of a dispensing system. The individual components are not mixed until they completely exit their individual

compartments - e.g., by moving past the tip or other exterior opening of their compartment.

[0009] Mixing generally occurs as the materials are dispensed through a motionless mixing nozzle, which functions as a static mixer. Nordson EFD of East Providence, Rl commercially supplies static mixers and related

components. As the dispensing step occurs proximate in time to the mixing step using conventional mixers, blockage of the dispensing system due to the working life of the resin being superseded is minimized in most applications.

[00010] Nevertheless, adequate mixing of components within a resin system is a concern in many applications, particularly those relying on dispensing of discrete and limited amounts of resin. In such applications, the presence of air bubbles and/or inadequate dispersal of additives or other components can be problematic. When the viscosity of components prior to mixing differs, for example in the case of alumina-filled resin systems, uniform and efficient mixing of the components is more difficult when using static and other mixers. For example, Brenda Jackson's January 2002 publication in Adhesives Age, entitled "Static Mixers: What users should know about their specification and application for adhesives," describes concerns associated with correct, efficient mixing of adhesives and sealants in packaging and supplying two-component reactive material systems using static mixers.

[00011] In order to improve these mixing issues, it is known to use planetary mixers, wherein mixer blades therein each rotate on their own axes, and at the same time on a common axis, thereby providing complete mixing in a very short timeframe. Planetary centrifugal mixers, such as those commercially available under the trade designation THINKY MIXER from Thinky USA (Laguna Hills, CA), are used for compounding of, for example, epoxy resin (two-part epoxy base resin plus hardener) and alumina powder. The use of such mixers is known to, for example, be beneficial for reduction of air bubbles in the resin system mixed therein. Bladeless mixers that are also known to be beneficial for reduction of air bubbles in the resin system mixed therein are also commercially available from FlackTek Inc. (Landrum, SC) under the trade designation,

SPEEDMIXER. The SPEEDMIXER technology involves dual asymmetric centrifugal mixing. Both of these mixers can be operated under a vacuum when so configured. From these mixers, material can be transferred into syringes or other dispensing cartridges, as desired.

[00012] Due to the many complications associated with adequate mixing and handling of multi-component resin systems, it is standard in the industry for pre-filled syringes or other dispensing cartridges to be provided in packaged form to end-users. This standard practice, however, is not without its own

complications.

[00013] In order to extend the working life of the packaged resin systems, it is generally necessary to store and ship the packaged resin at low temperature in order to prevent premature cure and, thus, inefficient or incapable use of the resin system. As such, it is common practice for end-users to receive packaged resin systems from suppliers using very expensive shipping methods, often entailing use of dry ice and overnight shipping methods.

[00014] Once application of the resin is desired, it must generally be thawed slowly in order to prevent development of air bubbles within the syringe or other dispensing cartridge. At all times, the packaged resin systems must be handled carefully in order to prevent premature localized heating of the container {e.g., syringe), which can cause the typically plastic material of the container to expand under the heat and create an air pocket thereunder.

[00015] In view of the above, alternative methods for mixing and dispensing of multi-component resin systems are desirable. Particularly desired are those methods eliminating the expensive and time-consuming standard practices involving storage and shipping of mixed resin systems at low temperature.

SUMMARY OF THE INVENTION

[00016] Resin system customers are able to readily mix resin system components on-site when their use is desired, thereby avoiding expensive and time-consuming standard practices involving storage and shipping of mixed resin systems at low temperature. An efficient kit for forming a ready-to-use multi- component resin system according to the invention comprises: a mixing vessel; a first resin system component contained within the mixing vessel; a second resin system component packaged in proportion for mixing with the first resin system component to form the multi-component resin system; a planetary mixer in which contents of the mixing vessel can be mixed; and at least one dispensing tool for the multi-component resin system. Using kits of the invention, a customer can efficiently form and use only the amount of resin system that is needed.

[00017] Methods of using the kit comprise sequential steps of: adding the second resin system component to the mixing vessel; mixing contents of the mixing vessel using the planetary mixer to form the multi-component resin system; and filling the dispensing tool with the multi-component resin system of the mixing vessel. Advantageously, kits and methods of the invention are generally more cost-effective than the industry standard practice involving storage and shipping of mixed resin systems at low temperature.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[00018] FIG. 1 A is a pictorial representation of one embodiment of a partial kit of the invention.

[00019] FIG. 1 B is an exploded view of the pictorial representation of FIG. 1 A.

[00020] FIG. 2 is a pictorial representation of prior art syringe and cartridge dispensing tool dimensions useful in the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[00021] According to the invention, kits for forming a ready-to-use multi- component resin system are provided. The kits comprise at least a mixing vessel; a first resin system component contained within the mixing vessel; a second resin system component packaged in proportion for mixing with the first resin system component to form the multi-component resin system; a planetary mixer in which contents of the mixing vessel can be mixed; and at least one dispensing tool for the multi-component resin system.

[00022] Any suitable planetary mixer, operable under atmospheric and/or vacuum conditions, can be beneficially used according to the invention. In a planetary mixer according to the invention, no blades, paddles, or shafts internal to the mixing vessel are used for mixing. One or more mixing vessels are placed in the planetary mixer. The mixing vessels rotate, as would blades, in conventional planetary mixers. That is, the mixing vessel(s) rotate on their own axes, and at the same time on a common axis, thereby providing complete mixing in a very short timeframe. Those of ordinary skill in the art are readily familiar with operation and/or instructions for use of such planetary mixers. In a preferred embodiment, the planetary mixer is operable under vacuum conditions. According to one aspect of this embodiment, the planetary mixer is operated under a vacuum of less than 50 Torr (6.7 kPa). According to a further aspect of this embodiment, the planetary mixer is operated under a vacuum of less than 100 Torr (13.3 kPa). While rotational speed and duration can vary, in one embodiment, the planetary mixer is operated within the range of about 200 to about 2,000 rpm for about 60 to about 180 seconds duration.

[00023] Exemplary commercially available planetary mixers include those available under the trade designation THINKY MIXER from Thinky USA (Laguna Hills, CA) and those available under the trade designation, SPEEDMIXER, from FlackTek Inc. (Landrum, SC). Depending on the end-user's requirements, the planetary mixer may be provided with the kit as leased equipment or using other temporary cost-effective arrangements. In any event, kits and methods of the invention are generally more cost-effective than the industry standard practice involving storage and shipping of mixed resin systems at low temperature.

[00024] Any suitable mixing vessel is provided in kits of the invention. The type of mixing vessel is generally not limited except with respect to its ability to be used in the planetary mixer within kits of the invention, so that no blades, paddles, or shafts internal to the mixing vessel are used for mixing. Preferably, the mixing vessel serves as the packaging for shipping and storage of the first resin component in addition to serving as a container for mixing of the resin system components. As such, in an exemplary embodiment, the mixing vessel is capable of being sealed for shipping and storage of the first resin component. Exemplary commercially available mixing vessels include those dispensing cartridges available from PPG Industries, Inc. (Sylmar, CA) under the SEMCO trade designation. [00025] The first resin component, if not already present, and any additional resin system components are added to the mixing vessel using any suitable equipment and methodology. Preferably, the filling equipment does not contact the interior of the mixing vessel. In one embodiment, additional resin system components are introduced into the mixing vessel using a positive displacement- type dispensing tool - e.g., a syringe, cartridge, or similar apparatus employing a plunger that can be operated manually or using air pressure. In an exemplary embodiment, the additional resin system components have a volume that is at least about 10%, even at least about 20% in a further embodiment, of volume of the first resin component in the mixing vessel. Thus, the mixing vessel is sized accordingly.

[00026] In one embodiment, the mixing vessel is sized so that the contents thereof are enough to fill only one dispensing tool. In another embodiment, the mixing vessel is sized so that the contents thereof are enough to fill no more than about twenty of the dispensing tools. In yet another embodiment, the mixing vessel is sized so that the contents thereof are enough to fill no more than about one-hundred of the dispensing tools. In general, the mixing vessel or contents thereof are limited in volume to that which prevents the multi-component resin system in the last-filled dispensing tool from being efficiently and capably dispensed from its dispensing tool.

[00027] Any suitable dispensing tool can be provided in kits of the invention. In an exemplary embodiment, the dispensing tool comprises a syringe. A number of commercially available dispensing tools are suitable for use in the invention, including syringe barrels and related components available under the trade designation, OPTIMUM, from Nordson EFT (East Providence, Rl). FIG. 2 illustrates conventional dimensions, in terms of respective diameters 202, 203 and lengths 204, 205 of syringes 200 and cartridges 201 , as set forth in the following Tables 1 and 2.

[00028] Table 1 - Conventional Syringe Dimensions Size Diameter Length

3cc 1 1 .1 mm (0.44 inch) 73.0 mm (2.88 inches)

5cc 14.3 mm (0.56 inch) 68.3 mm (2.69 inches)

10cc 19.1 mm (0.75 inch) 88.9 mm (3.50 inches)

30cc 25.4 mm (1 .0 inch) 1 15.9 mm (4.56 inches)

55cc 25.4 mm (1 .0 inch) 173.0 mm (6.81 inches)

[00029] Table 2 - Conventional Cartridge Dimensions

[00030] The dispensing tool is filled with contents from the mixing vessel using any suitable methodology and equipment. In one embodiment, dispensing tools of the invention are filled by way of positive pressure introduced from the mixing vessel. According to this embodiment, no vacuum is applied to the dispensing tool during the filling step. Preferably, the dispensing tool is filled via its tip, as opposed to being filled via a larger potential opening in the dispensing tool in which a plunger or similar apparatus is inserted and which is prone to introduction of air bubbles into the filled contents. As used herein, a "tip" is understood to be the opening in the dispensing tool from which contents are dispensed for final use in their intended application. Preferably, tips used in the invention have a luer, threaded, or similar fitting to facilitate ready attachment of needles, nozzles, or other dispensing aids to the dispensing tool. A luer tip 206 and a threaded tip 207 are illustrated in FIG. 2.

[00031] Kits may also further comprise an apparatus for assisting in filling the dispensing tool with contents from the mixing vessel. Preferably, such an apparatus enables rapid fill of the dispensing tool or multiples thereof. One such commercially available filling apparatus is that provided by Nordson EFT (East Providence, Rl) under the ATLAS trade designation. Other such commercially available filling apparatus are those provided by Thinky USA (Laguna Hills, CA) under the ARC-600TWIN and ARC-40 trade designations. Note that the contents of the mixing vessel, beginning with the first resin system component, do not exit the mixing vessel until they are directed into the dispensing tool, optionally with the assistance of a filling apparatus.

[00032] The components of the multi-component resin system vary depending on the application. A wide variety of multi-component resin systems are known, including those based on epoxy, polyurethane, silicone and methacrylate resin chemistries. In order to reap benefits associated with the invention, preferably the multi-component resin system is a thermosettable resin system. Preferably, the first resin system component contained within the mixing vessel in kits of the invention is the resin and the second resin system

component is a curative for the resin.

[00033] Of the wide variety of useful thermosetting resins, epoxy resins are particularly favorable. The most common epoxy resin types include those based on diglycidyl ether of Bisphenol A and the epoxy novolacs (comprised of glycidyl ethers of cresol novolac, phenolic novolac, or Bisphenol A novolac). However, lower viscosity epoxy resins, such as those based on the diglycidyl ether of Bisphenol F, are known and useful as well.

[00034] Generally, a curative is needed to effectuate final cure {i.e., thermosetting) of the multi-component resin system. Any suitable curative in any suitable form {e.g., powder or liquid) can be used in resin systems of the invention. As known to those skilled in the art, different curatives impart various advantages when used. For example, in epoxy systems, aliphatic amine curatives allow for room-temperature cure, whereas aromatic amines offer optimal chemical resistance and more rigid final parts. As another example, acid anhydride curatives can provide superior electrical properties. It is to be understood, however, that selection of the curative depends, among other well- known factors, on curing conditions desired and the intended application. An exemplary class of curatives useful for curing of epoxy resins is the modified aliphatic amine curatives such as those available from Air Products and

Chemicals, Inc. of Allentown, PA under the ANCAMINE trade designation {e.g., ANCAMINE 2441 ). Another class of curatives includes dicyandiamides, optionally with the use of common accelerators. For example, a useful combination is OMICURE DDA 5, an ultra-micronized grade of dicyandiamide, and OMICURE U-52, an aromatic substituted urea used as an accelerator for dicyandiamide cure of epoxies (both available from CVC Specialty Chemicals, Inc. of Moorestown, NJ). Another useful combination is AMICURE CG-1400, a micronized grade of dicyandiamide, and AMICURE UR, a substituted urea-based accelerator (1 phenyl 3,3 dimethyl urea) for dicyandiamide-cured epoxy resins (both available from Air Products and Chemicals, Inc. of Allentown, PA). Any suitable amount of the curative is used in resin systems of the invention.

Generally, after the specific type of curative is selected, the amount used is calculated as is well known to those skilled in the art.

[00035] In addition to basic components enabling formation of the multi- component resin system, a wide variety of optional additives can be present in the multi-component resin systems as known to those of ordinary skill in the art and depending on the application. In any event, it is preferred that all

components of the resin system be provided in proportioned quantities so that each packaged component can be mixed with other components of the kit in a one-to-one ratio {i.e., a ratio based on packages as opposed to a volumetric or weight ratio), avoiding the need for measuring and/or otherwise proportioning amounts of each component to be added to the mixing vessel by the end user. That way, mistakes in measurement and proportioning can be easily avoided when using kits of the invention.

[00036] Components of one embodiment of a partial kit 100 of the invention are illustrated in FIGS. 1 A and 1 B. As illustrated therein, a mixing vessel 102 is fitted into a stand and block 104. For filling the dispensing tool 106, a cartridge- to-barrel fitting 108 is positioned between the mixing vessel 102 and the dispensing tool 106. A plunger 1 10 with a fill level indicator 1 12 is fitted into the dispensing tool 106. Material is dispensed from the dispensing tool 106 via a tip 1 14. Opposite the cartridge-to-barrel fitting 108 is a toggle switch 1 16 for turning on/off material flow from the mixing vessel 102. A pressure regulator 1 18 regulates pressure within the mixing vessel 102 during the step of filling a dispensing tool 106.

[00037] An exemplary embodiment and application of the invention is described in the following non-limiting hypothetical example:

[00038] Example 1

[00039] Part A of a resin system is put into a cartridge - e.g., a 2.5-oz cartridge, the volume of which is large enough to accommodate part B of the resin system. Part B is put into a preportioned package. Both part A and part B are shipped to a customer as part of a kit of the invention. Advantageously, the resin system components need not be shipped with dry ice or any of the complications associated therewith. Prior to this point, or concurrent with the shipment, a planetary centrifugal mixer arrives at the customer's facility and is placed into operation. When use of the resin system is desired, the customer opens the cartridge containing part A and adds the part B package contents into the cartridge. That same cartridge is then placed into the planetary centrifugal mixer, and mixing is performed with the cartridge functioning as a mixing vessel. The walls of the cartridge function as blades in conventional mixing apparatus due to the high shear on the cartridge walls resulting from spinning of the mixer. No other device or blade comes into contact with the resin system components being mixed in the cartridge. As such, cleaning of mixer blades or other devices is not necessary.

[00040] Once mixed, the same cartridge is placed into an apparatus for filling the dispensing tool - e.g., a syringe filler - whereby the mixed resin system is moved directly from the cartridge into a syringe (typically of the size of 3cc, 5cc, 10cc, 30cc, 55cc, or 70cc). There is no contact of the mixed resin system with any part of the planetary centrifugal mixer, which negates the need to clean any part of the same due to its contact with the resin system components. There is no intermediate vessel into which the mixed resin system is transferred before passing into the dispensing tool, which minimizes risk of contamination and minimizes loss due to transfer. Using kits of the invention, a customer can efficiently form and use only the amount of resin system that is needed.

[00041] Various modifications and alterations of the invention will become apparent to those skilled in the art without departing from the spirit and scope of the invention, which is defined by the accompanying claims. It should be noted that, unless stated otherwise, steps recited in any method claims below do not necessarily need to be performed in the order that they are recited. Those of ordinary skill in the art will recognize variations in performing the steps from the order in which they are recited. In addition, the lack of mention or discussion of a feature, step, or component provides the basis for claims where the absent feature or component is excluded by way of a proviso or similar claim language.

[00042] Further, as used throughout, ranges may be used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. Similarly, any discrete value within the range can be selected as the minimum or maximum value recited in describing and claiming features of the invention.

[00043] In addition, as discussed herein it is again noted that the

composition described herein may comprise all components in one or multiple parts. Further, while reference may be made herein to preparation of the various intermediate components, recognize that some such intermediate components may be commercially available and, as such, may be usable according to the invention as an alternative to otherwise preparing the same. Other variations are recognizable to those of ordinary skill in the art. Note also that any molecular weights given herein are number average molecular weights unless specified otherwise. Further, any properties described or measured herein are those existing at room temperature and atmospheric pressure unless specified otherwise.

Claims

1 . A kit for forming a ready-to-use multi-component resin system, the kit comprising:

a mixing vessel;

a first resin system component contained within the mixing vessel;

a second resin system component packaged in proportion for mixing with the first resin system component to form the multi-component resin system; a planetary mixer in which contents of the mixing vessel can be mixed; and

at least one dispensing tool for the multi-component resin system.

2. The kit of claim 1 , wherein the mixing vessel is sized so that the contents thereof are enough to fill only the at least one dispensing tool of the kit.

3. The kit of claim 1 , wherein the mixing vessel is sized so that the contents thereof are enough to fill no more than about one-hundred of the dispensing tools.

4. The kit of claim 1 , wherein the mixing vessel is sized so that the contents thereof are enough to fill no more than about twenty of the dispensing tools.

5. The kit of claim 1 , further comprising a third resin system component.

6. The kit of claim 1 , further comprising an apparatus for filling the dispensing tool with contents from the mixing vessel.

7. The kit of claim 1 , wherein the dispensing tool comprises a syringe.

8. The kit of claim 1 , wherein the dispensing tool comprises a cartridge.

9. The kit of claim 1 , wherein the multi-component resin system is an epoxy resin system.

10. The kit of claim 1 , wherein the multi-component resin system is an alumina-filled epoxy resin system.

1 1 . The kit of claim 1 , wherein the first resin system component comprises a resin.

12. The kit of claim 1 1 , wherein the second resin system component comprises a curative for the resin.

13. The kit of claim 1 , wherein the mixing vessel serves as packaging for shipping and storage of the first resin component in addition to serving as a container for mixing of the resin system components.

14. The kit of claim 1 , wherein the dispensing tool comprises a luer tip or a threaded tip.

15. A method of using the kit of claim 1 , the method comprising sequential steps of:

adding the second resin system component to the mixing vessel;

mixing contents of the mixing vessel using the planetary mixer to form the multi-component resin system; and

filling the dispensing tool with the multi-component resin system of the mixing vessel.

16. The method of claim 15, further comprising the step of applying the multi- component resin system to a substrate.

17. The method of claim 15, further comprising the step of applying the multi- component resin system to a substrate after filling the dispensing tool and without freezing the filled dispensing tool.