WO2017136651A1

WO2017136651A1 - Molding compositions with functionalized graphene oxide

Info

Publication number: WO2017136651A1
Application number: PCT/US2017/016395
Authority: WO
Inventors: Michael Asuncion; Probir Kumar GUHA; David Krug; Michael J. Siwajek
Original assignee: Continental Structural Plastics, Inc.
Priority date: 2016-02-04
Filing date: 2017-02-03
Publication date: 2017-08-10

Abstract

A mold release compound is provided with superior conductivity compared to conventional metal-fatty acid salts for use in thermoset resin molding to produce articles that are amenable to electrostatic coating and other surface treatments that rely on surface conductivity. A thermoform molded article is provided that includes a thermoform resin composition having a bulk region and a surface region beyond the bulk region; and a functionalized conductive graphene oxide present in an amount in the surface region sufficient to render the surface conductive enough to be electrostatically coated. A method of making a sheet molding composite panel is provided that includes providing a sheet molding composite composition, and adding a mold release agent with a functionalized conductive graphene oxide. The release agent is added to the bulk of the sheet molding composite composition. During molding the mold release agent concentrates in a surface region of the molded article.

Description

MOLDING COMPOSITIONS WITH FUNCTIONALIZED GRAPHENE OXIDE

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority of United States Provisional Patent Application Serial No. 62/291,275 filed February 4, 2016, which is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates generally to molded articles with electrically conductive surfaces and methods of forming the same.

BACKGROUND OF THE INVENTION

[0003] Owing to customer visibility and environmental exposure encountered by certain vehicle parts, a high quality surface and paint finish is demanded that is commonly referred to in the industry as a Class A finish. To provide a high quality paint surface vehicle components such as doors, hoods, quarter panels, and other vehicle skin parts may be electrostatically painted. Electrostatic painting generally requires that the part be electrically conductive and support an electrical potential sufficient to attract oppositely charged paint droplets to the part's surface. However in many applications the polymer used to make the parts is not naturally conductive. As described in prior publications to make certain polymers electrostatically conductive the materials must be modified or enhanced. Electrically conductive polyester molding compositions suitable for electrostatic painting have been described in U.S. Patent No. 7,655297, the disclosure of which is incorporated herein by reference. As disclosed therein polymer compositions can be provided with a surface conductivity by adding conductive materials to the polymer composition. [0004] Care in the formation of the surface of a molded article is needed to make a class A surface. Thermoset resins such as sheet molding composites and bulk molding composites tend to adhere to mold surfaces which can detrimentally affect surface quality. To promote the molding process, manufacturers often resort to mold release agents that facilitate the release of the molded article from the mold. Internal mold release agents such as magnesium stearate and stearic acid have been used in sheet molding composites and bulk molding composites to promote release of the molded article from the mold. While mold release agents can provide both a physical and/or chemical barrier as a means of separation between the materials being molded and the mold surface, the mold release agents alone do not provide a conductive surface sufficient for electrostatic painting. As described in prior publications carbon black, graphite and other conductive materials can be added to the bulk composition to improve conductivity. The process of distributing a conductive material throughout the bulk material may be wasteful, as material addition to the bulk material may not serve a useful purpose. When changes to the base resin are needed the resin mixture has to be reengineered. Engineering a new resin mixture can be time consuming. Changes to formulate the mixture can also lead to tradeoffs in another properties. These tradeoffs can invariably lead to a need for re-optimization of the molding process. This approach can add significant cost and time.

[0005] Thus, there exists a need for a molding composition / molding process for thermoform resins, sheet molding composites or bulk molding composites that addresses one or more of the problems or improvements associated with conventional thermoform resin compositions, mold releases, surface conductivity, molding thermoform resin compositions and/or bulk resin properties. There also exists a need for a molding composition / molding process for thermoform resins, sheet molding composites and bulk molding composites that can provide a high quality surface with a surface conductivity created with less impact on resin molding properties and/ or finished product, bulk properties.

SUMMARY OF THE INVENTION

[0006] A thermoform molded article includes a thermoform resin composition having a bulk region and a surface region beyond the bulk region, and a compound of the formula GO-M-FA, where GO is graphene oxide, M is calcium, magnesium, zinc, or other 2+ valency metal ion chelated by a carboxyl group, and FA is a fatty acid carboxylate of an acid of stearic, myristoleic, palmitoleic, sapienic, oleic, elaidic, vaccenic, linoleic, linoelaidic, arachidonic, eicosapentaenoic, erucic, or docosahexaenoic. The thermoform molded article has a surface region that has a greater concentration of the functionalized conductive graphene oxide than the bulk region.

[0007] A method for producing a sheet molding composite article includes providing a sheet molding composition, adding a mold release agent to the sheet molding composite composition, the mold release agent being a compound of the formula GO-M-FA, where GO is graphene oxide, M is calcium, magnesium, zinc, or other 2+ valency metal ion chelated by a carboxyl group, and FA is a fatty acid carboxylate of an acid of stearic, myristoleic, palmitoleic, sapienic, oleic, elaidic, vaccenic, linoleic, linoelaidic, arachidonic, eicosapentaenoic, erucic, or docosahexaenoic, and molding the sheet molding composite composition with the mold release agent to produce the article. The sheet molding composite article formed has the mold release agent concentrated in a surface region of the molded article.

DESCRIPTION OF THE INVENTION

[0008] The present invention has utility as a mold release compound with superior conductivity compared to conventional metal-fatty acid salts. Particular utility is found in thermoset resin molding to produce articles that are amenable to electrostatic coating and other surface treatments that rely on surface conductivity.

[0009] It is to be understood that in instances where a range of values are provided that the range is intended to encompass not only the end point values of the range but also intermediate values of the range as explicitly being included within the range and varying by the last significant figure of the range. By way of example, a recited range of from 1 to 4 is intended to include 1-2, 1-3, 2-4, 3-4, and 1-4.

[0010] To address one or more needs in the art, disclosed herein are embodiments of a thermoform article and compositions, functionalized conductive graphene oxide, mold release agents and methods of making that have one or more features as presented in the embodiments and descriptions provided below which may be combined in total or separately.

[0011] Provided in the disclosure is a thermoform molded article including a thermoform resin composition having a bulk region and a surface region beyond the bulk region; and a functionalized conductive graphene oxide present in an amount in the surface region sufficient to render the surface conductive enough to be electrostatically coated. In one embodiment the thermoform molded article may have a surface region with a greater concentration of functionalized conductive graphene oxide than the bulk region. The thermoform molded article may be provided with a thermoset resin. The thermoset resin composition may include an unsaturated polyester or polyvinyl ester. The thermoset resin composition may be a sheet molding composite composition.

[0012] The functionalized conductive graphene oxide may include a fatty acid metal. The functionalized conductive graphene oxide may be a metal stearate. The functionalized conductive graphene oxide may include a metal ion. The functionalized conductive graphene oxide may also include a metal ion in addition to a fatty acid metal. [0013] Also provided in the disclosure are methods for producing a sheet molding composite panel. In one aspect of the disclosure there is provided a method of making a sheet molding composite panel including the steps of providing a sheet molding composite composition, and adding a mold release agent to it. The mold release agent may include a functionalized conductive graphene oxide. The release agent may be provided by adding it to the bulk of the sheet molding composite composition. During molding the mold release agent may concentrate in a surface region of the molded article.

[0014] In some embodiments, there is provided a thermoform resin composition including a conductive graphene oxide with at least one functional group associated with graphene oxide. A particular graphene oxide is a graphene oxide including a long chain fatty acid metal. The graphene oxide may include a metal ion. The modified graphene oxide can have a conductivity greater than 1 x 10^~3 S/m. The modified graphene oxide may be used as a mold release agent.

[0015] As defined in this disclosure conductive means a conductivity of lxlO^"3 S/m or greater. Thermoform resins include both thermoset and thermoplastic resins. Sheet molding composites are thermoset resin compositions reinforced with glass, carbon, or natural fibers. A mold release agent is an agent that imparts lubricity or surface dynamics in an amount sufficient to increase mold release capability over a comparable material lacking such material.

[0016] In a first embodiment there is provided a graphene oxide including a graphene oxide combined with an organometallic to produce a functionalized graphene oxide. The functionalized graphene oxide may further include on or more metals. An exemplary organometallic includes a long chain fatty acid metal. The functionalized conductive graphene oxide can have a conductivity greater than 1 x 10^~3 S/m. In use the functionalized conductive graphene oxide may be added to a thermoform molding composition to enhance surface conductivity and/or aid as a mold release agent. The functionalized conductive graphene oxide finds particular use in sheet molding composite applications.

[0017] Graphene oxide ("GO") may generally be represented by the following:

[0018] Graphene oxide platelets have chemically reactive oxygen functionality, such as carboxylic acid, groups at their edges (according to the widely accepted Lerf-Klinowski model), and epoxy and hydroxyl groups on the basal planes. One approach to the chemical modification of graphene oxide is to utilize reactions of these groups to selectively functionalize one site over another. At one extreme graphene oxide maybe electrically insulating due to its disrupted sp2 bonding networks. Because electrical conductivity may be provided by functionalizing graphene oxide in accordance with this disclosure, the product of this reaction may be a functionalized conductive graphene oxide.

[0019] Conductive properties in the surface of a molded article may be obtained with a sufficient amount of functionalized conductive graphene oxide. For example, 5 percent or more by weight of a functionalized conductive graphene oxide per weight of resin mixture may be sufficient. A sufficient amount can be provided with a functionalized conductive graphene oxide having a conductivity from 1 x 10^"3 to 10^s S/m at 20 C. Conductive properties in the surface of a molded article may also be provided with a functionalized conductive graphene oxide having a conductivity of 1 S/m or greater, lxlO² S/m or greater, lxlO⁵ or greater S/m or anywhere in between depending upon the application and desired outcome. Likewise surface conductivity of the thermoformed article may be achieved with a conductivity of 1 S/m or greater, lxlO² S/m or greater, lxlO⁵ or greater S/m or anywhere in the range using a functionalized conductive graphene oxide.

[0020] The modified or functionalized conductive graphene oxide may be made by combining a metal stearate and graphene oxide. The metal stearate may be combined at the carboxyl group of a graphene oxide (as represented by region C of the graphene oxide representation above) to create a modified or functionalized graphene oxide of a mixed metal stearate. Besides metal stearates other organometallics can be used including fatty acids other than saturated C₁₇, including myristoleic, palmitoleic, sapienic, oleic, elaidic, vaccenic, linoleic, linoelaidic, arachidonic, eicosapentaenoic, erucic, and docosahexaenoic. These are represented by the general formula, M- FA₂, which is intended to include M-St₂.

[0021] Metallic stearates have the general formula M-St₂. Metallic stearates are compounds of long-chain fatty acids with metals of different valences. Stearate starting material may be produced from organic raw materials. Metal stearates may be made using chlorinated hydrocarbons or vegetable and mineral oils and waxes. The stearate starting materials by themselves do not provide a sufficient conductive medium for electrostatic painting. Metallic stearates may be selected from the metallic stearates of calcium, magnesium and zinc. For example:

Ca-St₂ can be represented by the formula:

and may be produced by the reaction: 2 C17H35COOH + CaO ---> (Ci7H35COO)₂Ca + H₂0

[0022] Graphene oxide may be modified to include at least one functional group. The at least one functional group may be a substituted metallic stearate wherein the metal stearate M-S2 is modified to include a graphene oxide in place of one of the stearates. The modified graphene oxide may be represented by the general formula GO-M-FA wherein M-FA is selected from the group of metallic fatty acid salts (such as stearates) including one or more of calcium, magnesium and zinc, and other metals that chelate to carboxyl groups with a 2+ valency state.

[0023] The formation of a mixed metal stearate graphene oxide may be provided by reaction of a metal stearate in the presence of an amine or chelating agent and in the presence of graphene oxide. Metallic stearates may be provided in any suitable form, including fine powders, flakes, or granules. The functionalized graphene oxide metal stearate may be used as a lubricant and/or release agent. The functionalized graphene oxide metal stearate may be hydrophobic. Without desiring to be bound by theory it is postulated that in use the metal of the modified metal stearate graphene oxide may compete with the metal ions present in the compositional network to reduce the number of high energy sites available for bonding at the metal surface of the mold. As the metal surface energy is reduced, mold release can be improved.

[0024] In an exemplary embodiment an alkali earth (Mg or Ca)-stearate (M-St₂) is modified to include a graphene oxide in place of one of the stearates (St). The resulting molecule is expected to bring enough graphene oxide into proximity with the surface to exceed the percolation threshold so electrons could jump from one graphene oxide molecule to a contiguous one to achieve surface conductivity. This is expected to result in efficient usage of graphene oxide without interfering with conventional resins (unsaturated polyesters and polyvinyl esters). [0025] In use the functionalized graphene oxide may be added to a thermoform resin composition. Adding a functionalized conductive graphene oxide to a thermoform resin composition can help to facilitate electrostatic painting and can aid in making a body panel with a class A automotive finish.

[0026] In another embodiment there is provided a thermoform resin composition having a bulk region and a surface region beyond the bulk region wherein the surface region and bulk region have different final product, compositional make-up. In this embodiment the functionalized conductive graphene oxide is present in an amount in the surface region sufficient to render the surface conductive enough to be electrostatically painted. By having a mold release with a higher concentration near the surface region in comparison to the bulk region, the addition of mold release may not essentially affect viscosity of the base resin composition thereby avoiding negatively impacting mold flow characteristics. As designed the surface region of the thermoform molded article may have a concentration of the functionalized conductive graphene oxide greater than that of the bulk region. This can be made possible by functionalizing the graphene oxide with a structure that tends to separate from the bulk mixture or resist dispersement during the molding operation. As proposed, an exemplary functional structure is a metal organic and a more exemplary functional structure is a metal stearate. An inventive compound of the formula GO-M-FA is typically present in a thermoset resin from 0.05 to 5 total weight percent. Without intending to be bound to a particular theory, it is believed that GO-M-FA functions in a manner similar to a conventional metal stearate mold release with the proviso that surface conductivity is modified.

[0027] Graphene oxide, GO is commercially available or obtained from prepared processes such as chemical exfoliation of graphite with mineral acid and permanganate. The resultant suspension is washed and filtered to remove residual graphite and oxidizing agents. The resulting graphene oxide is dried to a flowable powder.

[0028] The thermoform molded article may be a thermoset resin. Suitable thermoset resin compositions include unsaturated polyesters or polyvinyl esters. A suitable composition of the thermoform resin mixture may include one or more enhancing ingredients including film formers, catalysts, binders, crosslinking agents, flow aids, catalysts, fillers, dyes, pigments, conductive particulates, and so forth. Particular advantage may be had in using the functionalized graphene oxide as a mold release agent with a sheet molding composite in addition to the one or more of the enhancing ingredients. An exemplary mold release agent is a functionalized conductive graphene oxide including a fatty acid metal or metal stearate. The thermoform molded article may also include a metal ion in addition to the metal stearate.

[0029] As generally described above the graphene oxide may include one or more metals, M' . The metal, M' may be added to increase conductivity. To make graphene oxide with one or more metals graphene oxide can be reacted with a chelating agent in the presence of metal ions. Suitable metals include those having a conductivity of greater than lxlO³. Suitable metals, M' may be selected from transition metals, alkaline earth metals or any other suitable metal. Metals may be selected from the group consisting of silver, copper, gold, calcium, tungsten, zinc, nickel, lithium, iron, platinum, tin, and titanium. The resulting molecule may bring enough graphene oxide and/or metal ion into proximity with the surface to exceed the percolation threshold so electrons could jump from one graphene oxide molecule to a contiguous one to achieve increased surface conductivity. By having a conductive graphene oxide it is expected to result in a more efficient usage of graphene oxide while not interfering with conventional resin properties or performance (unsaturated polyesters and polyvinyl esters). [0030] The metal ion may be added to the graphene oxide by any suitable means. For example, functionalized graphene oxide may be reacted with a suitable agent in the presence of metal ions to produce a functionalized conductive graphene oxide which can generally be represented by the following formula: FA-M-GO-M R where FA is a fatty acid salt, M is a 2+ valency metal ion, M' is a metal ion chelated solely by the GO and R is an optional organic chelate for M' . The metal may reside in the +1 or +2 valiancy states. The metal ion may bond with GO through the oxygen generally depicted in the GO representation shown above in region A. GO may be reacted in the presence of metal ions to produce a graphene oxide with a metal ion. Suitable reaction mechanisms include reacting the functionalized graphene oxide and metal ions in the presence of an amine.

[0031] The chelating agent R is provided in certain inventive embodiments to inhibit simultaneous chelation of a single metal ion by chelating moiety, such as carboxyl groups by multiple graphene oxide molecules. It is appreciated that some preparations of graphene oxide are able to chelate a given metal ion and a given loading without resort to an additional chelating agent and as a result, R in the above formula is not necessary and would be a nullity in the above formula. The chelating agent R, when present is mondentate, bidentate, or polydentate. Without intending to be bound to a particular theory, stearic effects associated with the separation between carboxyl groups on the graphene oxide molecule make it difficult to complete the coordination number for a given metal ion, leading to solvent coordination or chelation by carboxyl groups of other graphene oxide molecules; resulting is low stability chelation and increased viscosity, respectively. A chelating agent R is provided to displace coordinate covalent bonds with solvent or multiple graphene oxide molecules as needed. As subsequently detailed, titration with a chelating agent is readily accomplished to end points that illustratively include a decrease in viscosity, a color change, or a combination thereof. [0032] A chelating agent R operative herein illustratively includes alky lene amine acids, such as ethylenediamine disuccinic acid (EDDS), ethylenediamine dimalonic acid (EDDM), and ethylenediamine diglutaric acid (EDDG), ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), nitrilotriacetic acid (NT A), iminodiacetic acid (IDA), iminotriacetic acid (ITA), ethylenediamine (En), Ν,Ν'-diethylenediamine (Den), diethylenetriamine (DTN), diethyienetetramine (Trien), triaminotriethylene amine, citric acid, pyridine, pyrrole, and propylenediamine.

[0033] A sheet molding composite panel may be made by adding a mold release agent of the inventive compound to a molding mixture. The mold release agent may be added by any suitable means. The mold release agent may be blended with the bulk material of the pre-mold mixture or disposed about a surface region. The sheet molding composite may then be molded with the mold release agent to produce a molded article. In one embodiment where the mold release agent is added prior to the molding process, the mold release agent is concentrated in a surface region of the molded article. In the case where the mold release agent is a functionalized conductive graphene oxide including a fatty acid metal, the fatty acid metal functionalization can aid in either preventing dispersement into the bulk resin composition or facilitate aggregation of the conductive material in a surface region exterior of the bulk. Concentration of the conductive material in the surface region over that of the bulk region can provide a surface that is conductive with less conductive material in the bulk. By providing less conductive material in the bulk sufficient conductivity may be provided with less conductive material overall. Also by having less conductive material in the bulk the potential impact on resin properties can be reduced and material saving may be realized. As provided the method for producing a sheet molding composite with a functionalized conductive graphene oxide having an additional metal ion can also provide enhanced conductivity in an amount sufficient for electrostatically coating a molded article. The release agent functionality may also allow one to produce a coated article with a class A surface finish, such as one having a class A finish with a Diffracto analysis D number of less than 100.

[0034] The resin composition maybe include fillers and other additives including those generally known in the art while enhanced by a conductive mold release agent as disclosed herein.

[0035] Concentration of the functionalized conductive graphene oxide may be accomplished by any suitable means including heating or by application technique. A preferred depth of increased concentration is at a distance from the surface sufficient to affect panel release while making the surface conductive without having uniform concentration throughout the article. One way to accomplish a preferred depth of increase concentration is to provide a functionalized conductive graphene oxide mold release agent that has a relatively low solubility in the resin. In use the conductive mold release agent may be provided by dispersing it in a thermoform resin mixture. In another use the conductive mold release agent may be applied directly to a mold surface. The functionalized conductive graphene oxide mold release agent may be characterized by its characteristics of lubrication and release properties, as well as water repellency. The special effects of these properties can be determined by the cation, the chain length of the fatty acid and certain other properties of the respective organometallic. For example, the modified calcium stearate, magnesium stearate and zinc stearate may have varying stabilizing and processing aid effects in a wide range of thermoplastics.

[0036] The surface composition provided with a functionalized conductive graphene oxide may be particularly useful with electrostatic coating operations. The molded article may be electrostatic coated using any suitable technique. Suitable electrostatic coating techniques include using liquids and powders. Suitable liquid coatings include water-based and/or organic-based compositions. Using the method as disclosed above sufficient conductivity can be imparted to the article or substrate by incorporating the functionalized conductive graphene oxide prior to electrostatic coating. The electrostatic attraction between the coating material and the grounded article can result in a more efficient, thicker and consistent coverage with less wasted paint.

[0037] The present invention is particularly well suited for the production of a variety of products illustratively including bumper beams, vehicle door panel components, automotive floor components, spoilers, hoods, deck lids, body panels, and various industrial and consumer product housings such as cabinets, lockers, and pallets.

[0038] The present invention is further illustrated with respect to the following non-limiting examples:

Example 1

[0039] 5 mmol of sodium stearate (St) is dissolved in 100 ml of deionized water and an equimolar amount of GO is dissolved with pH adjustment as needed with NaOH to promote dissolution. 5 mmol of calcium chloride is added to precipitate a mixed GO-Ca-St compound.

[0040] The GO-Ca-St compound is combined into a base thermoset resin of TCA® Ultra Lite™ Continental Structural Plastics (Auburn Hills, MI, USA) at a 2 total weight percent in place of conventional Ca-St₂ and cured. The resulting formulation is cured into a plaque having a surface rich in graphene oxide and greater surface conductivity than a plaque formed from the base thermoset resin alone.

Example 2

[0041] The graphene oxide reaction with an epoxide procedure of Example 1 is repeated with graphene oxide chelated with an equimolar amount of Ag+-EDTA. The resulting plaque has greater surface conductivity than the plaques of Example 1. Example 3

[0042] The procedure of Example 1 is repeated with sodium linoleate in place of sodium stearate. The resulting resin cures and releases as does the article of Example 1.

[0043] Patent documents and publications mentioned in the specification are indicative of the levels of those skilled in the art to which the invention pertains. These documents and publications are incorporated herein by reference to the same extent as if each individual document or publication was specifically and individually incorporated herein by reference. While the claimed invention has been illustrated in the foregoing description, the same is to be considered as illustrative and not restrictive in character. Therefore, it should be understood that only exemplary embodiments have been shown and described and that all changes and modifications that come within the spirit and scope of the claimed invention are desired to be protected.

Claims

1. A thermoform molded article comprising:

a thermoform resin composition having a bulk region and a surface region beyond the bulk region; and

a compound of the formula GO-M-FA, where GO is graphene oxide, M is calcium, magnesium, zinc, or other 2+ valency metal ion chelated by a carboxyl group, and FA is a fatty acid carboxylate of an acid of stearic, myristoleic, palmitoleic, sapienic, oleic, elaidic, vaccenic, linoleic, linoelaidic, arachidonic, eicosapentaenoic, erucic, or docosahexaenoic.

2. The thermoform molded article of claim 1 wherein the surface region has a greater concentration of the functionalized conductive graphene oxide than the bulk region.

3. The thermoform molded article of claim 1 wherein M is calcium and FA is stearic acid.

4. The thermoform molded article of claim 1 wherein M is magnesium and FA is stearic acid.

5. The thermoform molded article of any one of claims 1 to 4 wherein the thermoset resin composition includes an unsaturated polyester or polyvinyl ester.

6. The thermoform molded article of any one of claims 1 to 4 wherein the thermoform resin composition is a sheet molding composite.

7. The thermoform molded article of any one of claims 1 to 4 wherein GO-M-FA is present from 0.05 to 5 total weight percent.

8. The thermoform molded article of claim 1 further comprising a metal ion chelated to the GO.

9. The thermoform molded article of claim 8 further comprising a chelating agent simultaneously bonded to said metal ion.

10. The thermoform molded article any one of claims 8 or 9 wherein said metal ion is silver.

11. A method for producing a sheet molding composite article comprising:

providing a sheet molding composition;

adding a mold release agent to the sheet molding composite composition, the mold release agent being a compound of the formula GO-M-FA, where GO is graphene oxide, M is calcium, magnesium, zinc, or other 2+ valency metal ion chelated by a carboxyl group, and FA is a fatty acid carboxylate of an acid of stearic, myristoleic, palmitoleic, sapienic, oleic, elaidic, vaccenic, linoleic, linoelaidic, arachidonic, eicosapentaenoic, erucic, or docosahexaenoic; and

molding the sheet molding composite composition with said mold release agent to produce the article.

12. The method of producing a sheet molding composite article of claim 11 wherein the mold release agent is concentrated in a surface region of the molded article.

13. The method of producing a sheet molding composite article of claim 11 wherein said mold release agent is present from 0.05 to 5 total weight percent.

14. The method of producing a sheet molding composite article of claim 11 further including electrostatically coating the molded article to produce a coated article with a class A surface finish having a Diffracto analysis D number of less than 100.

15. A compound of the formula GO-M-FA, where GO is graphene oxide, M is calcium, magnesium, zinc, or other 2+ valency metal ion chelated by a carboxyl group, and FA is a fatty acid carboxylate of an acid of stearic, myristoleic, palmitoleic, sapienic, oleic, elaidic, vaccenic, linoleic, linoelaidic, arachidonic, eicosapentaenoic, erucic, or docosahexaenoic.

16. The compound of claim 15 wherein M is calcium and FA is stearic acid.

17. The compound of claim 15 wherein M is magnesium and FA is stearic acid.

18. The compound of claim 15 further comprising a metal ion chelated to the GO.

19. The compound of claim 18 further comprising a chelating agent simultaneously bonded to said metal ion.

20. The compound of any one of claims 18 or 19 wherein said metal ion is silver.