Keith
KENT
Silicone Dental Coating
Silicone Dental Coating
http://www.kisscareultra.com
KISscare
ultra
A Non-Stick Coating for Natural teeth, Dentures, Implants and Dental restorations. Dental Plaques, foods and candy will not stick to KISSCare ULTRA treated surfaces.
Self-Bonding silicone polymer coating, catalytically modifies polydimethelsiloxane -- Aka dimethicone — into a polymer that has a methyl top layer- a silicone midlayer and an oxygen layer- that bonds to a substrate.
http://www.nature.com/bdj/journal/v216/n11/full/sj.bdj.2014.487.html
British Dental Journal 216 : 648 (June 2014)
13 June 2014 |
doi:10.1038/sj.bdj.2014.487
Non-stick
sealing and protection for teeth and dentures
Introduction
KISSCARE ULTRA creates a non-stick surface that seals and protects natural teeth and dentures from stains, sticky foods and plaque for up to six months.
KISSCARE ULTRA, from WDR Scientific in the US, resists acid, reducing the damaging effects of dental caries. It has also been shown to seal newly bleached tooth surfaces while acting as a desensitiser, protecting teeth from sensitivity.
KISSCARE ULTRA can easily be applied to natural or artificial teeth. It is a tasteless, non-toxic and non-flammable self-bonding polymer gel that works by turning the surface it is applied to into inert silicone. The gel can be applied without complicated tools or procedures on two full arches in less than ten minutes, using only a cotton swab, floss or a prophy cup. The product does not eliminate the need for normal oral hygiene.
More information about KISSCARE ULTRA can be found at www.wdrscientific
http://www.wdrscientific.com
where the product is also available for purchase and delivery worldwide.
KISSCare ULTRA TM is indicated for Sensitive teeth, Anti Staining and as a anti carries Tooth Sealant, KISSCare ULTRA TM is a Non-Stick surface coating that will resist microbial adherence, resist acids, resist sticky foods, candies and bacterial plaques from forming on natural teeth, restorations, implants and dentures.
KISSCare ULTRA TM and Statements contained herein have not been evaluated by the United States Food and Drug Administration for the treatment or cure of any disease.
The content of KISSCare ULTRA TM is pure POLYDIMETHYLSILOXANE, which is classified by the US FDA as GRAS or Generally Recognized as Safe.
http://www.wdrscientific.com/
Data
Sheets
http://www.wdrscientific.com/uploads/3/2/3/4/32346055/kiss_test_bleed_pdf.pdf
http://www.wdrscientific.com/uploads/3/2/3/4/32346055/reduce_or_eliminate_plaque_kisscare_ultra_2014.pdf
http://www.wdrscientific.com/uploads/3/2/3/4/32346055/kcareapp.pdf
http://www.dentalproductsreport.com/files/files/dpr0714_ezine.pdf
Dental
Products Report
July-2014 Page 76 Product Watch
July-2014 Page 76 Product Watch
US
Patents
US4623593
Self-adhesive polymer composition for use as prosthetic appliance
US4623593
Self-adhesive polymer composition for use as prosthetic appliance
Also published as: JPS6321063 // GB2192191 // DE3622767
Polymer compositions and methods of making them are provided. Selected surface layers of the polymers, integral with the polymer body, possess pressure sensitive adhesive properties. The polymers are cured with the selected surfaces in contact with a cross-linking inhibition agent which controls the amount of cross-linking of the polymer taking place at the surface. The polymers are useful as, or in conjunction with, prosthetic appliances which are adhered to skin or other substrates.
BACKGROUND OF THE INVENTION
This invention relates to polymeric compositions and their preparation, which compositions when cured have an integral permanently tacky surface layer, and more particularly to self-adhering polymers used as prosthetic appliances.
Our society places a heavy emphasis on physical attributes. Because of this, a person with a congenital, developmental, or acquired defect may be considered by some as socially unacceptable subconsciously, if not overtly. Such defects also affect a person's self-image. Since facial appearance and expression are both highly visible and a primary means of communication, defects of the head and neck areas are more socially traumatic than defects of other body parts. The preparation of maxillofacial prosthetics requires the use of both art and science in reconstructing defects using polymeric synthetic materials The goal of maxillofacial prosthetics is establishing function, fit, appearance, and physiology.
There are two general categories of maxillofacial prosthetics, namely, intraoral and extraoral. Intraoral prostheses are usually fabricated in association with a partial or complete denture. Retention of intraoral prostheses usually pose few problems except in a completely edentulous patient having markedly resorbed ridges, poor quality bony or soft tissue undercuts, and a bulky or weighty obturator. Extraoral prostheses pose more retentive as well as aesthetic problems. A major problem for a patient wearing an extraoral prosthetic device is the potential for dislodgement, and concomitant patient embarassment during normal activity.
A number of different types of polymeric materials have been utilized as base materials for prostheses. Principal among these polymers have been the silicone rubbers and polyurethanes. These elastomeric polymers are used for most extraoral prostheses because of the life-like qualities that can be imparted to them. These qualities include flexibility and the ability to be colored. This coloring is accomplished by adding fibers or pigment to the prepolymer or by tattooing the completed prostheses to conform them closely to the skin tones of the areas contiguous to the reconstructive site.
The chemical inertness of these polymers once cured is a major factor in their popularity in maxillofacial prosthetic reconstruction. However, the same chemical inertness and inherently non-stick properties which makes polymers such as silicone rubbers desirable prosthetic materials also is the cause of the majority of difficulties in working with them. While in some cases the use of surgery to provide tissue undercuts to aid in mechanically retaining a prosthesis is possible, in many other cases adhesives alone, or in combination with other mechanical retention aids such as wires, elastics, or eyeglasses, must be used as the primary means for retention. For example, a prosthetic ear may have virtually no other means for retention than an adhesive. This is also true in most cases where the defect is large or cannot be surgically modified to provide mechanical retention.
At the present time, we know of no completely satisfactory and medically safe adhesive for routinely securing, and regularly detaching for hygienic purposes, prosthetic devices. The problems of applying adhesives to and retaining them on inherently non-stick surfaces, such as silicone rubber, are readily apparent. These problems are compounded by the presence of surface contaminants such as dirt, oils, and dead skin on the tissue to which the prosthetic device is to be applied. Once cured, many adhesives no longer are sticky and will not bond again after removal. Also, many adhesives that have pressure sensitive properties lose their adherent properties once their surface has been contaminated.
Accordingly, the need exists in the art for medically acceptable polymer compositions suitable for use as prosthetic devices which possess permanently adherent, properties and which can be repetitively applied and detached from human skin or other surfaces.
SUMMARY OF THE INVENTION
The present invention meets this need by providing polymer compositions, and methods for their preparation, with integral surface layers having permanently tacky, pressure sensitive adhesive properties and which are suitable for use as prosthetic appliances. Many polymeric materials are useful in the practice of the present invention, with preferred polymers being those which are cured or vulcanized by a crosslinking reaction of monomeric, prepolymeric, or unvulcanized polymeric components and mixtures thereof. Most preferred for use as prosthetic appliances are so-called "medical grade" compositions which are physiologically inert.
We have found that an integral surface layer having pressure-sensitive adhesive properties may be formed on an otherwise fully cured polymeric body. This may be accomplished by applying a sufficient amount of a cross-linking inhibition agent to selected surfaces of a mold cavity prior to packing the cavity with uncured monomeric, prepolymeric, or unvulcanized polymeric material. The mold is then closed and the material cured. The cross-linking inhibition agent acts on the surface or surfaces of the polymer to prevent complete cross-linking thereof. The body of the polymer is otherwise completely cured and has the same properties as would be expected. Conventional additives such as fibers and fillers may be added to the uncured compound and have no effect on the integral surface layer which is formed.
However, the surface or surfaces of the polymeric body which were cured in contact with the cross-linking inhibition agent remain tacky and possess pressure sensitive adhesive properties. We believe that these pressure sensitive adhesive properties result from the absence of complete cross-linking of the surface layer of the polymeric body. Thus, the surface of the body presents a multiplicity of elastomeric "fingers" or "hairs" which are an integral part of an otherwise completely cured polymeric body. We believe that it is the multiplicity of "fingers" or "hairs" and their chemical nature which, when placed in contact with a substrate, cause the polymeric body to adhere to the substrate.
The polymeric composition of the present invention has particular utility when used as a prosthetic appliance for attachment to human skin. The appliance can be repetitively applied and detached from skin, or other surfaces, without loss of effectiveness of its adhesive properties. Because the adhesive surface layer is integral with the body of the appliance, little or no adhesive will debond or leave a residue on the skin or other surface. Additionally, simple washing of the adhesive surface layer with soapy water or solvents such as acetone or alcohol will effectively remove any built-up contaminant layers of oils, greases, dirt, or undesirable biota. After drying, the original adhesive quality of the surface will be restored.
Accordingly, it is an object of the present invention to provide apolymeric composition having an integral surface layer with pressure sensitive adhesive properties useful in prosthetic appliances. This and other objects and advantages of the invention will become apparent from the following detailed description and the appended claims.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Many polymeric materials may be applicable in the practice of the present invention. Examples of polymers previously used in or as prosthetic appliances include acrylics, polyurethanes, silicones, polyesters, polyolefins, polyacrylamides, and polyether-urethane copolymers. Other suitable, medically acceptable polymers are also well known to those skilled in the art. We have found that the surface of a polymeric material can be modified by the practice of the present invention to give that surface pressure sensitive adhesive properties even though the remainder of the body of the polymer exhibits no adhesive properties and may, in fact, exhibit so-called "nonstick" properties. Silicone rubbers are a prime example of this. The polymers presently preferred in the practice of the present invention are silicone elastomers and specifically polydimethylsiloxanes because of their ready availability and acceptance for medical applications.
Without wishing to be limited to any specific theory or mechanism, we believe that the application of certain agents, which we will term cross-linking inhibition agents, to one or more selected surfaces of a mold cavity will inhibit the degree of cross-linking which occurs on the surface of the polymeric composition during a curing or vulcanization step. This results in a surface layer which presents a multiplicity of elastomeric polymer chains which at one end are integral with the body of the otherwise fully cured polymer but at the other end are free. We have found several suitable cross-linking inhibition agents including cyanoacrylate polymers and metal salts of carboxylic acids such as stannous octoate. Those skilled in the art may determine other suitable cross-linking inhibition agents by simple testing.
The polymer compositions of the present invention are preferably cured or vulcanized in a mold to form a variety of shapes and prosthetic appliances. A preferred material for the mold is dental stone, although other mold materials such as metals or the like may be used. After fabrication of the mold, the cross-linking inhibition agent is applied to one or more selected surfaces of the mold cavity, namely those surfaces which correspond to surfaces on the finished polymer or prosthetic appliance for which a pressure-sensitive adhesive surface layer is desired. The cross-linking inhibition agent may be applied by any suitable means such as brushing or spraying and allowed to dry. In many instances, the ease of application of the cross-linking inhibition agent may be enhanced by the use of a solvent such as acetone or alcohol. The amount of cross-linking inhibition agent applied will affect the depth of the surface layer having pressure sensitive adhesive properties which is formed. By modifying the amount of cross-linking inhibition applied to the surface of the mold cavity one can control the surface adhesive properties on the cured polymer.
After the cross-linking inhibition agent is dried, the monomeric, prepolymeric, or unvulcanized composition is packed into the mold cavity and the mold closed.
Depending upon the particular composition utilized, vulcanization or curing is then carried out at temperatures and times sufficient for the body of the composition to cure completely. Curing times and temperatures for specific compositions are well-known to those skilled in the art. For example, if silicone rubber is being cured, it may be a room temperature vulcanizing rubber or one that requires the application of heat (e.g., 150 DEG-250 DEG F.). Conventional additives such as fibers or fillers may be premixed with the uncured composition.
After curing has been completed, the mold is allowed to cool (if necessary) and the finished composition or prosthetic appliance is removed. The surface or surfaces of the polymer body which were cured in contact with the cross-linking inhibition agent will exhibit pressure sensitive adhesive properties, whereas the body of the polymer will otherwise exhibit those properties (i.e., strength, tear resistance, etc.) which would be expected of a fully cured polymer.
The surface layer of the polymer retains its pressure sensitive adhesive properties for the life of the polymer and remains integrally attached thereto. The surface layer may be secured to human skin or other substrates and repeatedly detached and reattached. If the surface layer becomes contaminated with oils, dirt, or undesirable biota, it may be readily cleaned and restored to its original state after drying by washing it with soapy water, acetone, or other suitable cleaning agents.
In order that those skilled in the art can better understand how the present invention can be practised, the following nonlimiting examples are given by way of illustration.
EXAMPLE 1
A mold was fabricated using air mixed dental stone (commercially available under the designation of Denstone from Columbus Dental Manufacturing Co., Columbus, Ohio) and a water/powder ratio of 30 cc/100gm. Selected surfaces of the mold cavity were painted with a cross-linking inhibition agent comprising a mixture of stannous octoate and denatured alcohol (1:10 ratio) and allowed to air dry. The mold cavity was then packed with a catalyzed, deaerated silicone prepolymer designated MDX4-4210 and commercially available from Dow Corning Corp., Midland, Michigan. The silicone prepolymer is believed to be a polydimethylsiloxane based silicone elastomer. After the mold was closed, vulcanization was accelerated by heating the mold at 200 DEG-220 DEG F. for approximately 2 hours. After the mold was cooled, the resulting polymer body was removed.
The silicone rubber body exhibited the expected physical properties of a fully cured material except for those surfaces which had been cured in contact with the cross-linking inhibition agent. Those surfaces exhibited tack and pressure sensitive adhesive properties.
EXAMPLE 2
The surface of a dental stone mold (Denstone) was cleaned successively by application of soap and water, carbon tetrachloride, chloroform, and methanol and then air dried. A cyanoacrylate alpha-or iso-cyanoacrylate cross-linking inhibition agent was applied to selected surfaces of the mold and allowed to air dry. The mold cavity was then packed with a catalyzed, deaerated silicone prepolymer (MDX4-4210) and the mold closed. The silicone was vulcanized by heating the mold at 80 DEG C. for 24 hours. After cooling, the polymer body was removed from the mold. The surfaces of the polymer which were cured in contact with the cross-linking inhibition agent were tacky and exhibited pressure sensitive adhesive properties.
The same experiment was run under the same conditions as above with the exception that the mold was packed with the silicone prepolymer before the cross-linking inhibition agent had dried. After 24 hours, the polymer had not cured indicating that the cyanoacrylate should be allowed to dry before the mold is packed.
EXAMPLE 3
The surface of a dental stone mold was cleaned as in Example 2 above and dried. A cyanoacrylate (alpha- or iso-cyanoacrylate) cross-linking inhibition agent was applied to selected surfaces of the mold and allowed to air dry. The dry cyanoacrylate was then coated with the catalyst for MDX4-4210 and the catalyst allowed to dry.
The mold was then packed with catalyzed, deaerated MDX4-4210 silicone prepolymer and vulcanized as in Example 2. The resulting polymer surfaces which had cured in contact with the cross-linking inhibition agent and catalyst were tacky and exhibited pressure sensitive adhesive properties.
EXAMPLE 4
The procedure of Example 3 was repeated except that a stannous octoate catalyst was applied over the dried cyanoacrylate and the silicone prepolymer packed in the mold was GE RTV11 (commercially available from the General Electric Co.). Again, the surfaces of the polymer body which had cured in contact with the cross-linking inhibition agent and catalyst were tacky and exhibited pressure sensitive adhesive properties.
EXAMPLE 5
The procedure of Example 3 was repeated except that a stannous octoate catalyst was applied over the dried cyanoacrylate and the silicone prepolymer packed in the mold was Silastic 382 (commercially available from Dow Corning Corp.). Once again, the surfaces of the polymer body which had cured in contact with the cross-linking inhibition agent and catalyst were tacky and exhibited pressure sensitive adhesive properties.
US4839456
Self-adhesive, drag reducing polymeric coating
Self-adhesive, drag reducing polymeric coating
A self-adhering polymeric composition for use as a drag-reducing fouling-release coating and a method for making such composition. The composition, which is formed by mixing a base polymer with a curing catalyst and immediately adding trace amounts of a inhibitor modifier to the mixture, produces a high integrity coating with a surface extended network of differentially cross-linked chains that reach into and control the flow/adhesion properties in the liquid phase.
BACKGROUND OF THE INVENTION
The present invention relates to polymeric compositions and, more particularly, if directed towards self-adhering polymeric composition for use as a drag reducing
coating.
Various coatings have been developed for reducing drag between two surfaces in relative motion. For example, U.S. Pat. No. 2,937,976 discloses a drag reducing gel for a razor blade and U.S. Pat. No. 4,385,134 teaches use of a drag reducing, antifouling coating for boat hulls.
The primary cause of drag on boat hulls is the growth of marine organisms on the hull. Generally, antiflouling coatings contain a toxicant agent which controls the growth of marine organisms. In such coatings it is necessary to control the amount of toxin delivered to the surface coating in order to prevent premature depletion of the antifouling agent. Other patents relating to drag reducing compositions for boat hulls include U.S. Pat. Nos. 3,575,123; 3,896,753; and 3,990,381. A need has arisen for an improved drag reducing coating for marine use which does not require use of a toxicant agent.
Also, there is a need for drag reducing composition which can be readily manufactured in form which can be easily applied to the surface of the object to be protected. Such a drag reducing composition should ideally be paintable or sprayable on the object surface and act to protect the underlying surface from degradation by bacterial decay, oxidation, water seepage and the like. Once such a drag reduction and/or protective coating is applied to an object surface, the coating should readily adhere to the surface, remain in such adherence, and itself be relatively inert to ambient sources of degradation.
SUMMARY OF THE INVENTION
In accordance with the invention there is provided a mothod for producing a polymeric composition comprising the steps of: bulk mixing a base polymer forming material with a catalyst; immediately adding trace amounts of a cross-linking inhibitor to the bulk mixture; and curing and polymerizing the inhibited bulk mixture.
The base polymer forming material preferably includes one or more of a monomer unit of a polymer, a prepolymer of polymer, or an unvulcanized form of the polymer which is preferably selected from the group of silicones, polyrethanes, polyacrylics, polyesters, polyolefins, polyacrylamides and polyether-urethane polymers.
There is also provided a method for producing a drag reducing polymer composition comprising the steps of: selecting a base compound comprising polymer forming units bulk mixing the base compound with a catalyst in an amount sufficient to polymerize essentially all of the polymer forming units; and adding a cross linking inhibition agent to the bulk mixture. In one example, the cross linking inhibition agent is added immediately after the step of bulk mixing is carried out. The cross-linking inhibition agent is preferably added in an amount sufficient to inhibit cross-linking to a predetermined degree. The mixture is typically subjected to polymerization conditions, such as heating, mixing, solution in solvent and the like, for a predetermined amount of time sufficient to effect predetermined amount of polymerization
and cross-linking.
The base compound typically includes unvulcanized silicon based polymers, and the inhibition agent is preferably added in a trace amount. The mixture of polymer forming material may be allowed to begin polymerizing, but only a slight degree, before the inhibition agent is added.
In accordance with the invention there is also provided a blend of one or more of a selected monomer, a prepolymer of the monomer, and a polymer of the monomer; a catalyst for causing unpolymerized components of the blend to polymerize and cross-link with the catalyst being added to the blend in an amount sufficient to polymerize and cross-link essentially all of the unpolymerized components of the blend; and a trace amount of a modifier which inhibits cross-linking, wherein, in one embodiment, the modifier is added to the blend and the catalyst essentially immediately after the blend. The monomer preferably comprises a monomer unit of one or more of a silicone, polyurethane, acrylic, polyester, polyolefin, polycrylamide or polyether-urethane copolymer.
An integral surface layer having pressure-sensitive adhesive properties may be formed on an otherwise fully cured polymeric body by applying a sufficient amount of a cross-linking inhibition agent to selected surfaces of a mold cavity prior to packing the cavity with uncured monomeric, prepolymeric, or unvulcanized polymeric material. The mold is then closed and the material cured. The cross-linking inhibition agent acts on the surface or surfaces of the polymer to prevent complete cross-linking thereof. The body of the polymer is otherwise completely cured and has the same properties as would be expected of a fully polymerized and cross-linked composition. Conventional additives such as fibers and fillers may be added to the uncured compound and have no effect on the integral surface layer which is formed.
In applications where selected surfaces of a polymerized body are treated with inhibition agent, the surface or surfaces of the polymeric body which are cured in contact with the cross-linking inhibition agent remain tacky and possess pressure sensitive adhesive properties. The present invention deals with treatment of the bulk prepolymer rather then treatment of selected surfaces of the prepolymer.
Accordingly, it is an object of the present invention to provide a self-adhering polymeric composition for use as a drag reducing coating. Self-adhering as used in this application means that the composition will adhere to a surface to be coated without special treatment of the surface.
It is another object of the present invention to provide a self-adhering polymeric composition for use as a fouling release, drag reducing coating.
It is a further object of the invention to provide a method for forming a self-adhering composition for use as a drag reducing coating. The coating is produced by inhibiting and permanently arresting the process of curing of a polymer. The method of forming the polymeric composition includes the steps of mixing a base polymer with a catalyst, and adding trace amounts of a modifier to the mixture. Preferably, the resultant composition is heated to accelerate the polymerization process. The resulting composition is a high integrity coating with all the useful engineering features of the bulk polymer with a surface network of differential cross-linked chains that reach into and control the flow/adhesion properties in the liquid phase.
Other objects, features and advantages will be apparent from the following detailed description of preferred embodiments:
DESCRIPTION OF PREFERRED EMBODIMENTS
The drag reducing polymer composition of the invention may be produced from a base polymer composition any one or more of a selected unvulcanized polymer, a prepolymer thereof, a monomer unit of the selected polymer or a mixture of one or more or all of the foregoing. The polymers, prepolymers thereof and monomer units of such polymers preferred for use in producing the drag reducing composition include silicones, polyurethanes, polyacrylics, polyesters, polyolefins, polyacrylamides and polyetherurethane copolymers. The polymers presently preferred in the practice of the present invention are silicone elastomers and specifically polydimethylsiloxanes because of their ready availability.
The base polymer composition is mixed in bulk with a catalyst which catalyzes both straight chain polymerizaton and cross-linking. The catalyst selected is typically peculiar to catalysis of the selected monomer units of the polymers to be formed, and is preferably added in an amount sufficient to polymerize and/or cross-link essentially all of the polymer forming material of the base polymer composition. In the case, for example, where a silicone polymer composition is to be formed, the selected base polymer composition including catalyst may comprise one or more MDX-4-4210, SILGARD 194, AND SILGARD 196 silicone prepolymers commercially available from the Dow Corning Corp., GTE RTVII, a prepolymer commercially available from the General Electric Co. In the case of MDX-4-4210, one part of the catalyst is mixed with each ten parts by weight of the base material. The catalysts employed for polymerization of such base compositions, catalyze a condensation reaction between the silicon elements which are typically bonded to one or more hydroxy or halogeno elements.
When the catalyst and base polymer forming units are mixed in bulk, a modifier, typically an inhibition agent, is added to the mixture. Preferably, the modifier is added to the mixture essentially immediately after the mixing of the catalyst and base polymer forming units. In one example, trace amounts of an inhibitor is added to the bulk mixture of the base polymer and catalyst. Where silicone prepolymer compositions are employed, the process is most preferably assisted by heating the base polymer/catalyst/modifier mixture to at least about 100 degrees Centigrade for at least about 20 minutes. Preferred modifiers, which are imcompatible with the normal polymerization process and permanently inhibit and arrest polymerization before it is completed, include metals salts of carboxylic acids, most preferably stannous
octoate.
The consistency of the drag reducing polymer composition may be controlled by controlling the degree of polymerization. The degree of polymerization may be controlled by accelerating or decelerating the conditions favoring polymerization such as by increasing or decreasing temperature for longer or shorter periods of time, allowing the base composition to begin polymerization to some predetermined degree before adding an inhibition agent, increasing or decreasing the amount of catalyst and the like.
The resulting drag reducing composition may range in consistency from a wax-like substance to a runny liquid depending upon the predetermined degree of polymerization allowed. Preferably the composition is produced in such a consistency that the resulting mixture may be directly painted on the surface of an object to be protected.
Notwithstanding the physical consistency of the resulting mixture, the mixture may be thinned, i.e., dissolved, in conventional organic solvents such as fluorocarbons, hydrocarbons, ethers, ketones and the like, to any predetermined degree to aid in the ready application of the resulting drag reducing polymer composition. In any event, once the composition is inhibited, polymerization is permanently arrested. Application of additional catalysts, heat or other standard modalities will not cause further vulcanization of the composition.
Without wishing to be limited to any specific theory or mechanism, we believe that the application of certain agents, which we will term permanent cross-linking inhibition agents, will permanently inhibit the degree of cross-linking of the polymeric composition which occurs during a curing or vulcanization step. This results in a multiplicity of elastomeric polymer chains. Several suitable cross-linking inhibition agents specific to prepolymers such as MDX4-4210 include metal salts of carboxylic acids such as stannous octoate. Prepolymers such as MDX4-4210; SILGARD 184 and 186; and SILASTIC 31-10, 31-12 and 31-20 are compatable with inhibitors such as chlorinated and butyl rubbers; most other room temperature vulcanizing (RTV) silicone rubbers; sulphur containing solvents; plasticizers; and tin containing compounds. Prepolymer such as SILASTIC 382, General Electric RTV-11 are compatable with inhibitors such as oxidizing oils; linseed oils; putties; oil containing clays; and plastizers, specifically amine containing plasticizers. Those skilled in the art may determine other suitable cross-linking inhibition agents by simple testing.