CZ62394A3 - Method of enhancing adhesive properties of adhesives and sealing materials - Google Patents

Abstract

The improved adhesion is provided by incorporating into an adhesive and/or sealant plastic material an effective amount of cyclodextrin or a complex of cyclodextrin and blowing agent. Where the complex of cyclodextrin and blowing agent is employed, an expandable mixture is formed.

Description

The present invention relates to adhesives and sealants, and more particularly to a method for improving the adhesive properties of adhesives and sealants, as well as adhesives and sealants that are currently characterized by increased tack. The invention has proven to be particularly suitable for expanded adhesives and sealants where blowing agents have traditionally been used.

BACKGROUND OF THE INVENTION

Blowing agents, which are sometimes referred to as foaming agents, are substances which produce a cellular structure in a liquefied preparation on a plastic or rubber substrate. Common blowing agents include fluorinated hydrocarbons, nitrogen gas, hydrazine derivatives, trihydrazine triazines, 5-phenyltetrazole, p-toluenesulfonyl semicarbazide, modified azodicarboxamides and azodicarboxamides. Chemical blowing agents form a group of blowing agents and are solid or solid at room temperature. after heating, they release gas. A well known group of chemical blowing agents is sold under the trade name CELOGEL (Uniroyal, Inc).

Blowing agents are commonly used in the production of a wide range of consumer products and self-sealing sealants. Furthermore, blowing agents are used together with the adhesive plastic materials in the hot melt adhesive. Furthermore, blowing agents are also used in the packaging of foodstuffs, as is the case with parts of animals as cut by the butcher with a view to resale. Such a product is usually referred to as a bone cut.

Chemical blowing agents are typically used by mixing the blowing agent with a solid plastic material and then heating the mixture while keeping the mixture under pressure. By heating the plastic material to liquefy and also the gas is released from the blowing agent · This then forms bubbles or empty voids in the liquefied plastic material ·

Chemical blowing agents have the advantage over gaseous blowing agents, such as nitrogen or certain fluorocarbons, that they can be injected into the liquefied plastic material as compared to the gaseous blowers.

For hot melt adhesives and sealants, the gas is mixed with the adhesive composition before the nozzle orifice.

The use of fluorocarbons as blowing agents has been the subject of severe criticism with regard to the adverse effects on the ozone layer of the earth. Handling, toxicity and flammability issues with other common blowing agents · Stability in storage, dustiness and explosion hazards include handling problems ·

SUMMARY OF THE INVENTION

It has now been found that the use of cyclodextrins in adhesive and sealant compositions improves the adhesive quality of such a composition. It has also been found that the cyclodextrin-blowing agent complex functions as a blowing agent in the liquefied adhesive and / or adhesive material, as well as improving the adhesive properties of the adhesive or sealant. In addition, cycloddextrin stabilizes the blowing agent · It has also been found that some chemical compounds which have not been used in this sense have been used as blowing agents.

The process of the invention comprises mixing the cyclodextrin with an adhesive or sealant plastic material, wherein the prepared mixture is applied to the surface. When

-3The increasing volume of the adhesive or sealant comprises the step of preparing a mixture of adhesive and / or sealant of the plastic material and the blowing agent and cyclodextrin complex by heating the mixture to liquefy the plastic material to release gas from the complex. they form empty tubes in the liquefied plastic material.

The step of forming the cyclodextrin chemical blowing agent complex is performed before the complex is stirred. into plastic material.

The mixture is heated either using heat, as is typically the case with conventional extrusion or blow molding processes, or an exothermic reaction such as polyurethanes can be utilized.

The adhesive or sealant composition prepared in accordance with the present invention comprises an adhesive or sealant plastic material and a blowing agent / cyclodextrin complex. As mentioned hereinbefore, it has been found that the adhesive property of the adhesive or sealing composition is improved in the presence of a cyclodextrin in the composition. Thus, the cyclodextrin appears not only as a support for the blowing agent, but also as a tackifier or adhesion promoter.

The amount of cyclodextrin that is added to the adhesive and / or sealing plastic material is an effective amount that improves the adhesion of the adhesive and / or sealing material. Preferably, the amount of cyclodextrin is added to the adhesive and / or sealant to improve its adhesion. Most preferably, the addition of from about 1 to about 10 parts cyclodextrin to the adhesive and / or sealing plastic material appears to improve the corresponding adhesion. The amounts indicated correspond to the amounts of the dextrin-blowing agent complex added to the adhesive and / or sealing plastics material in accordance with the present invention.

A mixture of cyclodextrins and adhesive and / or sealing material or a mixture of a cyclodextrin complex with a blowing agent and adhesive and / or sealing plastic material can be prepared using any mixing process as used for adhesive and / or sealing materials.

Cyclodextrins, also referred to as Schardinger ' s dextrins ¹ ', cycloamyloses, cyclomaltoxy and cycloglucans, are oligomeric anhydroglucose, linked to each other by -1-1,4-bonds to form ring structures. If it contains 6 glucose residues, it is referred to as o (β-cyclodextrin when 7, i.e. β-cyclodextrin and δ-β-cyclodextrin).

Cyclodextrins are conveniently prepared by treating the starch suspension with an enzyme or acid to form a gelatinous or liquefied slurry having a DE value of between 1 and 5. The product thus obtained is then treated with a cyclodextrin-glucosyltransferase at a suitable pH, temperature and time to suit cyclodextrin-glucosyltransferase used. This enzyme is obtained from microorganisms such as Bacillus macerans B. megaterium, B. circulans. Stearothermophilus, and Bacillus sp. (aliphatic) as well as others. The obtained extract for the treatment of the gelatinous or liquefied starch slurry by the action of cyclodextrin glucosyltransferase is then separated and purified in order to obtain cyclodextrins.

One very important aspect of cyclodextrins is their ability to act as clathrates or carriers of other compounds or substances. Physically, the cyclodextrin is shaped with a depression. as a result, it can serve as a clathrate for substances whose outer geometric dimensions correspond to the diameter of the cyclodextrin depression. The outer surface of such substances can be modified by various side chains, as is the case with the hydroxypropylcyclodextrin with shaping

-5in the cyclodextrin cavity surface. The term cyclodextrin as used in the present invention and the appended claims means not only cyclodextrin per se, but also modified and branched cyclodextrins.

As used herein and the appended claims, the term complex or cyclodextrin complex and blowing agent means not only an assembly of cyclodextrin and a blowing agent wherein the cyclodextrin carries the blowing agent, but also when the blowing agent is tightly attached to the outside of the cyclodextrin by weak binding forces. .

The process / complexing between the cyclodextrin and the blowing agent depends on dissolving the cyclodextrin in water together with the blowing agent, then filtering off the precipitated product.

Another method is to fill the ball mill with a cyclodextrin and a blowing agent, and to fill the mill for a certain time in the mill. This forms a complex of cyclodextrin and blowing agent. Another known process for forming a cyclodextrin-host molecule complex is in kneading, lyophilization, and grinding. product with both components. Good results are also achieved by crushing together in a mortar using a pestle.

The cyclodextrins used in the process according to the invention are of the type (β-i / i) β-cyclodextrins which are advantageous in view of their commercial availability, and the complex formed by combining all three cyclodextrins is characterized by differing speeds at which This is believed to be due to different binding forces of the blowing agent and different cyclodextrins.

Suitable blowing agents include liquids such as water, propylene glycol dipropylene glycol, tripropylene glycol, cyclohexylamine, dicyclohexylamine and ethylene glycol, as well as solids such as benzoyl peroxide and other peroxides, but are difficult to handle. It is surprising and quite unexpected that water, propylene glycol, dipropylene glycol, tripropylene glycol, as well as ethylene glycol are useful substances as non-blowing agents _o Until now, substances such as water, propylene glycophosphate, poor dispersibility in plastic materials ·

Solids, such as benzoyl peroxide, are difficult to use in such processes due to the low decomposition temperatures. Both water and propylene glycol should be considered safe and non-toxic to humans. Many of the numerous and common blowing agents are toxic to humans. The use of non-toxic blowing agents in the workplace brings about a very high degree of safety in the workplace, which has not been known until now. Using a combination of two or more blowing agents such as water and propylene glycol or using different cyclodextrins with the same blowing agents

In addition, conventional chemical blowing agents such as hydrazine derivatives, triazine trihydrazides, 5-phenyltetrazole, p-toluenesulfonylsemicarbazide, modified azodicarboxamides and azodicarboxamides which complex with cyclodextrins may be used as blowing agents in accordance with the process of the present invention. complex with cyclodextrin reduce dustiness and stabilize the whole product ·

The amount of blowing agent used to form the complex with c-yclodextrin is from about 1 to 30 parts per 100 parts by weight of cyclodextrins by weight. More preferably, the ratio is from about 3 to 15 parts, but most preferably from about 5 to about 7 parts by weight. cyclodextrin ·

An excess amount of blowing agent can be used to prepare the cyclodextrin-blowing agent complex.

A suitable source of cyclodextrin-water complex is cyclodextrin from the conventional cyclodextrin preparation processes. It usually contains about 10 to about 12 weight percent

-7-piece water. The use of such a cyclodextrin in the adhesive composition provides sufficient gas evolution upon heating of the commercially available cyclodextrin complexed with about 10 to 12 parts water as a blowing agent.

In general, it has been found that the smaller the particle size of the complex, the more uniform the size of the voids formed. Good results in this respect are achieved by using a cyclodextrin-blowing agent complex, the particles of which are capable of passing through 0.075 mm orifices in size

Suitable plastic materials include polymers such as polystyrene, polyvinyl chloride, polyethylene, polyurethane, polyphenols, polypropylene, polyisoprene (rubber), polybutadiene, as well as corresponding copolymers such as copolymer of acrylic acid, butadiene, butadiene, styrene, styrene and isoprene. , ethylene and butylene, styrene and butadiene as well as ethylene and vinyl acetate. A specific example of an adhesive plastic material is ethylene vinyl acetate, a copolymer of acrylic acid nitrile with butadiene and styrene, as well as styrene with isoprene. Good results in the process of the present invention are obtained by applying ethylene vinylation

Typical adhesive compositions in accordance with the present invention include ⁴ ethylene vinyl acetate modified resin waxes all adhesive plastic material antioxidant filler complex blowing agent and cyclodextrin

Weight parts 25-50 25-60

0-30

100 ALIGN!

0.05-0.5 parts 0-100 parts 1-10

The bookbinding adhesive composition of the present invention has the following composition:

Parts by weight ethylene vinyl acetate modified resin plasticizer wax plastic adhesive material, total antioxidant blowing complex with cyclodextrin antifungal agent (optionally)

35-45

20-30

20-30

10-20

100 ALIGN!

0.05-0.25

1-10

1-10

The blowing agent-cyclodextrin complex is preferably a cyclodextrin-water complex containing between 8 and about 15 parts by weight of water. The amount of the complex to be used in the bookbinding adhesive is in the range of about 3 to 7 parts with a water content of between about 10 to 15 parts.

The use of a microbial or fungicidal agent complexed with a cyclodextrin - when added to the adhesive composition - aids protection and prevents degradation, i.e. degradation of the agent. The water acts as a blowing agent and aids in the release of the microbial agent or fungicide.

The bookbinding adhesive is prepared by mixing all the listed and necessary components in a conventional manner.

The temperature of such adhesives ranges from about 120 ° C to about 20 ° C.

The use of a water-cyclodextrin complex has some advantages over the prior art using liquid nitrogen. Current machinery for use in hot melt for bookbinding requires a special machine design that permits the use of liquid nitrogen. By using the cyclodextrin-water complex of the present invention, a much larger selection of devices can be used.

Furthermore, the opening time of the book is longer, the surfaces are much better contacted, and less adhesive has to be used to cover the same surface.

The adhesive for closing cartons and boxes in accordance with the present invention comprises

Parts by weight ethylene vinyl acetate 40 modified resin 40 wax 20

Plastic adhesive material, total 100 antioxidants 0.01 blowing agent complex with cyclodextrin 1-10

Preferably, a propylene glycol-cyclodextrin complex containing from about 8 to about 15 parts of propylene glycol is used as the cyclodextrin blowing agent complex. Preferably, from about 3 to about 7 parts of this complex with a propylene glycol content of from about 10 to about 13 parts is used.

Carton and box closure adhesive is prepared by mixing all the components together in a conventional manner.

The temperature of these carton and box closure adhesives ranges from about 175 ° C to about 20 ° C.

The carpet reinforcing adhesive composition of the present invention comprises:

Parts by weight ethylene vinyl acetate 25-50 modified resin 25-60 waxes 0-30 plastic adhesive material (total) 100 antioxidants 0.05-0.5 filler 0-100 blowing agent and cyclodextrin complex 1-10

-10The blowing agent-cyclodextrin complex as used in this carpet reinforcing adhesive is a cyclodextrin complex with about 8 to about 15 parts water, propylene glycol or a combination of water and propylene glycol or a combination of water, propylene glycol and hydrazine derivatives.

Further, such a carpet-reinforcing adhesive preferably comprises a cyclodextrin-antifungal complex in an amount of up to about 1 part. Suitable antifouling agents include diiodomethyl-1-p-tolylsulfone, phenols and butylhydroxytoluene: diiodomethyl-1-p-tolylsulfone is preferred and the release of this substance can be influenced by water as it is released from the cyclodextrin.

The carpet reinforcing adhesive is prepared by mixing all the components together in a conventional manner.

The temperatures for use in the carpet reinforcement composition are in the range of about 65 ° C to about 70 ° C.

It has been found that due to the presence of cyclodextrin in these various adhesives and sealants, the adhesive nature of the sealant or adhesive composition also increases.

A small amount of an enzyme, known as amylose, when added to the expandable plastic composition of the present invention acts as a catalyst upon heating and accelerates the release of the blowing agent from the cyclodextrin. If the amylase is to act as a catalyst, there must be some water in the plastic composition. It is believed that amylase will utilize water to destroy and disrupt the cyclodextrin and thereby, and even accelerate, the release of the blowing agent.

It goes without saying that other substances can be added to the plastic materials containing the blowing agents of the invention, for example antifungal agents, fungicide OL fragrances.

DETAILED DESCRIPTION OF THE INVENTION

These and other aspects of the invention work better

-the linden tree with reference to the examples below,

Example 1

This example describes a hot melt adhesive composition in accordance with the present invention with a specific book binding purpose.

Bookbinding Material Parts by weight ethylene vinyl acetate-507 45 Staybelite resin 25 Pentalyn H 20 microcrystalline waxAll all bookbinding material 100

0.1 parts of antioxidant and 1θ parts of water and (3-cyclodextrin) complex are added to the adhesive plastic material; this complex contains 7.5 g of β-cyclodextrin and 2.5 g of water. Water can be complexed into cyclodextrin by mixing excess water After mixing the adhesive plastic material with the antioxidant and the water complex with the? -cyclodextrin, the mixture is heated to 100 ° C, at which point the water changes from a liquid phase to a gas, causing the adhesive agent to expand. % of the adhesive is about 100%.

Ethylene vinyl acetate-507 is a commercially available copolymer of ethylene and vinyl acetate (Union Carbide Co) · Staybelite resin is a hydrogenated resin and a plasticizer based on diethylene glycol esters and hydrogenated resins (Hercules Powder Co) _o Pentalyn H is a synthetic resin (Hercules Powder Co). Microcrystalline wax is a commercially available wax (Petrolite Co., Tulja, Oklahoma).

-12—

Irganox 1010 from Ciba-Geigy Co. is used as an antioxidant. -Cyclodextrin was a commercial product from the American Maize-Products Company (Hammond, Indiana).

Ordinary tap water is used as the water.

It is surprising and unexpected that the cyclodextrin-water complex was effective in the form of this formulation because the water used as such did not appear at all as a blowing agent in this bookbinding adhesive formulation.

Example 2

This example describes the preparation of an adhesive composition for cartons and boxes in accordance with the present invention.

Material Parts by weight ethylene vinyl acetate-305 40

CKM-2400

Piccolyte A-115 12.5

Super STATAC 12,5 polyvosk 1000 10 castor wax 10 plastic adhesive material, total 100

0.1 parts of the antioxidant and 1 part of the propylene glycol with β-cyclodextrin complex are added to the adhesive plastic material, which complex contains 1 mole of β-cyclodextrin and 2 moles of propylene glycol, which is formed by mixing excess propylene glycol with β-cyclodextrin.

The mixture of adhesive material, antioxidant and propylene glycol / β-cyclodextrin complex thus heated becomes propylene glycol from liquid to gaseous, which results in an increase in the volume of the adhesive composition.

The volume of the mixture increases by about 100%.

Ethylene vinyl acetate-305 is a commercially available copolymer of ethylene and vinyl acetate (Union Carbide). The CKM-2400 is also a Union Carbide product. Piccolite A-115 is a thermoplastic terpene resin (Hercules). Super STATAC is from Reichold Chemical Inc. Polywax 1000 was obtained from Bareco and Castor Wax from Universal Preservachems. Irganox 1010 was used as an antioxidant. Cyclodextrin was a commercially available product from the American Maize-Products Company (Hammond, Indiana). Propylene glycol was a commercially available product (Dow Chemicals).

It is both surprising and unexpected that the propylene glycol / cyclodextrin complex was effective in this formulation because when propylene glycol was used as such, it did not act as a blowing agent at all.

Example 3 *

In this example, the preparation of a carpet reinforcing agent in accordance with the present invention is discussed. The corresponding adhesive composition was prepared as follows:

Material parts by weight ethylene vinyl acetate 50 modifying resin λ 40 voids 10 plastic adhesive material (total) 100 antifungal agent (optional) 1-10

0.1 parts of antioxidant, about 20 parts of filler and 5 parts of water-cyclodextrin complex together with 5 parts of propylene glycol-cyclodextrin complex are added to the adhesive plastic material. The blowing agent and cyclodextrin complexes are prepared according to the above procedures of Examples 1 and 2. The blowing agent and cyclodextrin complexes are mixed with the adhesive formulation simultaneously using the procedures of Examples 1 and 2 hereinabove.

When the adhesive composition with both blowing agents is heated to about 195 ° C, the adhesive composition is expanded.

Ethylene vinyl acetate was a commercially available product, i.e. a copolymer of ethylene and vinyl acetate. The modified resins were commercially available wood resins, waxes commonly used in such treatments. The antioxidant was Irganox ΙθΙΟ and conventional calcium carbonate was used as a filler.

Example 4

This example describes an adhesive composition in accordance with the present invention.

The following adhesive product was purchased:

citli

Material ethylene vinyl acetate 501 ethylene vinyl acetate 605 ester Staybelite 10

Weight parts 15 30 37

Abitol 18 Plastic adhesive (total) 100

0.1 parts of Irganox antioxidant 10.10, 5 parts of water-cyclodextrin complex as well as 5 parts of cyclohexylamine and (3) -cyclodextrin complex are added to the adhesive materials. The water-bycododextrin complex contains 12.8 parts of water. The cyclodextrin α / cyclohexylamine complex, a volatile corrosion inhibitor, contains 8 parts of cyclohexylamine complexed with cyclodextrin. The complexes are prepared as well as admixing the components of the adhesive composition in accordance with Example 1.

The moisture release is a starting mechanism whereby the cyclohexylamine bound to the complex is partially released so that it is in equilibrium with the released moisture from the water-cyclodextrin complex. Such a mechanism provides corrosion protection on the metal surface. Cylclodextrin complex

-15a cyclohexylamine stabilizes cyclohexylamine during the heating process.

Cyclohexylamine, if not bound in the complex, is not stable in heating the adhesive composition. Ethylene vinyl acetate 501 and 605 were commercially available copolymers of ethylene and vinyl acetate (Union Carbide). Ester Staybelite 10 and Abitol were products from Hercules Co. · Temperature when used in the range of 65-75 ° C.

Example 5

The preparation of an expandable, curable sealant in accordance with the process of the present invention is described.

A. Hot Melt Substrate

Folder Parts

Kraton PC 1901 x (Shell) 100

Regalrez 1018 (Hercules) 270

Endex 155 (Hercules)

Irganox 10 (Ciba-Geigy) 1

B. Plasticizer ¹ overlaid with calcium sulphonate (Witco) 10 complex of H-cyclodextrin and dicyclohexylamine (molar ratio 2; 1)

Aluminum paste (50 to 50 aluminum in sunpar

2280 (Sun Oil) cyclodextrin with 10-13% water

Equal amounts of hot-melt substrate and ficator shells are mixed and after cooling, the mixture is applied to a cold rolled steel plate or a cold galvanized steel plate, the plates are transferred to an oven and heated.

The material expands on the surface in both directions, both vertically and horizontally, so that the mixture is doubled in volume.

Example 6

A mixture of 50 parts of the hot-melt substrate of Example 5 as described above and 50 parts of the overlaid calcium sulphonate is prepared by heating the second component, the calcium salt, before mixing to evaporate water therefrom. The mixture is then applied to a rolled steel or cold-galvanized steel plate and heated in an oven at 200 ° C _for 15 minutes. _O The mixture is thawed by heating and spilled on the plate without increasing its volume.

Adhesion Comparison of Examples 5 and 6

The material of Example 6 was evaluated for adhesion to a cold rolled and galvanized steel plate as compared to the material of Example 5 herein above. It was found that the material of Example 6 could be easily peeled from the plate while the material of Example 5 (hence the present invention) could not be easily removed.

Example 7

A mixture is prepared as in Example 6 herein above, with the change that the water does not evaporate from the coated calcium sulfonate before mixing and applying to a cold plate of rolled and galvanized steel plate and before heating in an oven at 200 ° C. The composition of this example rapidly * hardened in place.

-17Curing has accelerated due to water leakage, as evidenced by the complete immobility of the mixture and the deformation of the material placed on the plates.

Example 8

A mixture was prepared as in Example 6, but the mixture was not allowed to cool. The mixture is placed on a cold rolled steel or galvanized steel sheet, all placed in an oven at 200 ° C. This material is about twice as large in volume. The blowing agent (water), was in the cyclodextrin and released Tyr During the heating together with cyclohexylamine (the vapor phase corrosion inhibitor) ₀ Water cyclodextrin is controlled and is not available for curing, if not enough heat to trigger its release.

Example 9

Conventional sealing material is prepared as follows:

Components Kraton RD 6501 (Shell), 100 Regaltez 1018 (Hercules) 270 Bndex 155 (Hercules) 50 Irganox ΙθΙΟ (Ciba-Geigy) 1

This material is applied cold on a rolled steel plate or galvanized steel plate and these are placed in an oven at 200 ° C for 15 minutes. This material melts and spills over the plate.

Example 10

In the example, a mixture of the ingredients of Example 9 is used to prepare the sealing material of the present invention:

-18Parts Components

Mixture of Example 9 10 (β-cyclodextrin (10-13% water) 2

This is placed on a cold plate of rolled or galvanized steel and then heated to 200 ° C for 15 minutes. This sealant expands by volume, but by no means 100% of the original volume.

Adhesion Comparison of Examples 9 and 10.

The adhesion to steel plates of the material according to example 9 were compared with the adhesion of _the Example 10 has been found that the sealant of Example 10 (present invention) adhered to the steel plate better than the product of Example 9th

The sealant of Example 10 was also tested for relative adhesion to a cold and galvanized steel plate, stating that the material adheres better to the rolled plate compared to the galvanized plate.

Example 11

Another chemical blowing agent complexed to a cyclodextrin is disclosed herein

Folder Parts

Mixture of Example 9 10? -Cyclodextrin-dibutylstannidilaurate complex 2? -Cyclodextrin (10-13% water) 2

After mixing, the mixture is applied to a cold plate of rolled and galvanized steel and heated in an oven at 200 ° C for 15 minutes. This material also expanded by heating by about 100% compared to the original volume.

-19Additional comparison of examples 9 and 11.

Adhesion to steel plates of materials in accordance with Example 9 was tested against the materials of Example 11 and it was found that the material of Example 11 (ie, the present invention) adhered much better to the metal plates compared to the sealant of Example 9.

The sealant of Example 11 was also tested for relative adhesion to cold rolled and galvanized steel, with the result that the material of Example 11 adhered better to the rolled steel plate than to the galvanized plate.

Example 12

The example describes the use of a cyclodextrin-benzoyl peroxide complex as both a blowing agent and a cured agent for thermoplastics. The following product was prepared:

Preparation Quantity

A. Pusabond C D198 (DuPont) 10 g cyclodextrin-benzoyl peroxide complex (10% benzoyl peroxide content) 1 g

B. Pusabond C-D198 10 g

C-r Pusabond C-D198 10 g

Q-cyclodextrin (10% water) 1 g

D. Pusabond C-D198 10 g benzoyl peroxide 0.1 g

Each of the compositions was mixed under heating and sheets of uniform thickness were extruded while still in the liquid state. Parts of exactly the same length and weight were cut from the leaves and transferred to the furnace at temperature

-20200 ° C.

The blending of uncomplexed benzoyl peroxide resulted in bubble formation. This was not observed when the benzoyl peroxide-.beta.-cyclodextrin complex was stirred under the same conditions. In both formulations the amount of benzoyl peroxide was the same. It was also difficult to achieve uniform distribution of uncomplexed benzoyl peroxide during mixing.

The .beta.-cyclodextrin-benzoyl peroxide complex is mixed readily and uniformly distributed as the composition is stirred.

Very severe differences were observed after heating. Composition D, containing uncomplexed benzoyl peroxide, cured very rapidly and did not spread to the surface to any appreciable extent. The bubbles of the cured composition were not uniform in size or distribution «

Composition A, containing a cyclodextrin-benzoyl peroxide complex, also cured rapidly and also did not spread too much in the lateral direction. Swelling and curing occurred simultaneously. This composition rose higher than Sample D containing uncomplexed benzoyl peroxide. The bubbles in composition A were uniform in size and distribution. *

Composition C expanded laterally much more than any other. Water released from the cyclodextrin gave rise to bubbles of uniform size and distribution. The water that was released acted as a traditional blowing agent, but there was no curing agent to cure the composition and delay its spread.

Compound B was later spread more than Compositions A and D, but not so much as Compound C. There was no curing agent to delay

There was no clearing of the composition and also there was no blowing agent to assist in this spillage.

Best results were obtained with composition A containing a complex of benzoyl peroxide and -cyclodextrins. The benzoyl peroxide was stabilized so that it was released by heating to act as both a curing agent and a blowing agent. This complex is also easily mixed and dispersed into the composition.

It is to be understood that we intend to protect all changes and modifications to the preferred embodiment of the present invention which are set forth herein to illustrate the process and do not depart from the scope of the invention.

Claims (15)

l A method of increasing _the adhesive properties of the material, comprising: forming a composition comprising an adhesive and / or sealing plastic material and an effective amount of a cyclodextrin-blowing agent complex, and heating said composition until the plastic material used and the blowing agent expands said plastic material in a liquefied state. The method according to claim 1, wherein prior to formation in of said mixture, a step of forming a complex of the blowing agent used and said cyclodextrin _{o is carried out} The method of claim 1, wherein said cyclodextrin is -cyclodextrin. The process according to claim 1, wherein one or more of water, propylene glycol, dipropylene glycol, tripropylene glycol, ethylene glycol, cyclohexylamine, dicyclohexylamine and a peroxide are used as blowing agents. * The method of claim 1, wherein about 1 to about 30 parts by weight of said complex is blended into the plastic material used, calculated on a weight basis of 100 parts plastic material used. A method of increasing the adhesive properties of adhesive and / or sealing material, comprising the steps of: (a) adding an effective amount of cyclodextrin to said adhesive and / or sealing material; and b) mixing said adhesive and / or sealing plastic material with a cyclodextrin to form a smgsi with enhanced adhesion · The method of claim 6, wherein said cyclodextrin is β-cyclodextrin. The method of claim 6, wherein the amount of said cyclodextrin that is added to the adhesive and / or sealing plastic is from about 1 to about 30 parts by weight per 100 parts of said plastic. The method of claim 6, wherein said adhesive material is an ethylene-vinyl acetate copolymer. An enhanced adhesion and / or sealing composition comprising an adhesive and / or sealing plastic material and an effective amount of cyclodextrin. The adhesive and / or sealing composition according to claim 10, wherein the adhesive plastic material is an ethylene-vinyl acetate copolymer. Adhesive and / or sealing composition according to claim 10 wherein said cyclodextrin is used in said adhesive composition in an amount of from about 1 to about 30 parts by weight based on the weight of the paste material used. * An adhesive and / or sealing composition with improved adhesion, comprising an adhesive and / or sealing plastic material and an effective amount of a cyclodextrin-blowing agent complex. The adhesive and / or sealant composition of claim 13, wherein said complex is present in said composition in an amount by weight of from about 1 to about 30 parts by weight calculated on the plastic material. 15 Dec The adhesive and / or sealing composition according to claim 1 -2413, wherein said blowing agent is in said complex within the range of about 1 to about 30 parts by weight, based on 100 parts of cyclodextrin;