CA2164376A1

CA2164376A1 - Polymeric composition in pellet form

Info

Publication number: CA2164376A1
Application number: CA002164376A
Authority: CA
Inventors: Kevin J. Sweeney; Christopher E. Olson; Freddie C. Carter; James R. Farmer
Original assignee: HB Fuller Licensing and Financing Inc
Current assignee: HB Fuller Licensing and Financing Inc
Priority date: 1995-12-04
Filing date: 1995-12-04
Publication date: 1997-06-05

Abstract

A polymeric composition in pellet form suitable for molding articles is disclosed. The composition comprises:
a) A tacky hot melt composition comprising;
1) at least one high molecular weight triblock copolymer of the general configuration A-B-A; and 2) a plasticizer; and b) a pelletizing aid. The pelletizing aid substantically surrounds the tacky composition such that the molded articles are substantially free from surface tack.
A method of forming the pellets is also disclosed.

Description

A POLYlVIERlC COMPOSITION IN PELLET FOR~I

Field Of The Invention This invention relates to a polymeric composition in pellet form comprising a high 5 molecular weight block copolymer having the general configuration A-B-A, and a molecular `
weight greater than about 200,000. Specifically, it relates to a hot melt composition in pellet form having special properties especially suited for molding.

Background Of The Invention Hot melt pressure sensitive compositions have been used widely in the adhesive industry due to their ability to adhere to a wide variety of substrates. Block copolymers are the preferred polymer base due to their good heat stability, high cohesive strength, and compatibility with a wide range of tackifiers and plasticizers. A primary property of a hot melt pressure sensitive composition is that it remains tacky at room temperature and can be adhered to substrates when it has completely cooled from its molten state.
Applications requiring this property include labeling. Paper, polyethylene, polypropylene or other such substrates may be coated with the hot melt pressure sensitive adhesive, covered with release liner, and then shipped for later applications of labels, such as those used on various containers, books, magazines, or envelopes just to name a few.
The fact that pressure sensitive hot melt compositions remain tacky at room --temperature has precluded their use in a variety of other applications such as molding. One such application is the formation of articles by injection molding. Injection molding is used to form various articles such as shoe soles, drum pads, therapeutic hand exercising grips, shock absorbers, acoustical insulators, chair pads and so on.
The tackiness of these hot melt pressure sensitive compositions also makes them difficult to handle. They may adhere to skin, clothing, application equipment, floors and so on.
This is undesirable. Many packaging methods therefore, have been devised to avoid the problems encountered in the handling of these hot melt pressure sensitive compositions. Such methods include supplying them in pellet and pillow forms as disclosed by German Pat. 22 48 046. Slats or chicklets, blocks and cakes are also disclosed.

21~76 French Pat. No. 2,544,654 published October 26, 1984 discloses forming a tackless hot melt by adding the molten hot melt to a mold which contains a preformed support layer having a transfer film which is compatible with the hot me}t.
U.S. Pat. Nos. 4,748,796 issued June 12, 1988 and 4,755,24S issued July S, 1988 5 disclose forming a protective coating for an adhesive material by electrostatically coating a mold or cavity with a powder screen and then pouring hot melt into the mold.
French Pat. No. 2,601,616 published October 22, 1988 discloses forming blocks of hot melt pressure sensitive adhesive by casting the adhesive into molds precoated by spraying with a film of non self-sticking hot melt material.
Gerrnan Pat. Nos. DE 31 38 222, DE 32 34 065 and DE 36 25 358 teach coating or wrapping a formed hot melt block with various types of film.
U.S. Pat. No. S,257,491 to Rouyer et al. teaches a method of packaging a hot melt adhesive composition with a film wherein the adhesive composition is flowable at the time of packaging. It also discloses packaging adhesive compositions after solidifying or even 15 coextruding the adhesive .with the packaging material. The packaging material does not interfere with the properties of the adhesive composition during application.
U.S. Pat. No. 5,373,682 to Hatfield et al. issued December 20, 1994 teaches a method for packaging hot melt adhesive compositions by directly pouring or purnping the molten adhesive into a cylindrical plastic tube being in contact ~vith a heat sink. The adhesive package 20 is provided in a readily handeable, cartridge forrn which may be produced in a continuous line operation. The adhesive is fused to some extent with the film and in turn allows some mixing and compatibilizing of the film, improving the opportunity for more complete mixing.
U.S. Pat. No. 4,645,537 and 4,576,835 to Garderlier et al. disclose an aqueous release agent for hot melt pressure sensitive adhesives and a method for applying the same to hot melt 25 pressure sensitive adhesives. It was desired in Gardenier that the antiadhesive or nontacky surface be temporary. The pressure sensitive adhesive of Gardenier show no substantial difference in physical characteristics before and after addition of the release agent.
U.S. Pat. No. to Durbin et al. discloses the interfacial polymerization of one polymer onto a second polymer to provide a non-tacky, non-porous outer coating or shell to prevent _- 2164376 blocking and water entrapment. This teaches using condensation polymers to forrn a protective coating on the polymer, but have no permanent effect on the surface tack of the polymers, and therefore can be used in pressure sensitive hot melt adhesives.
U.S. Pat. No. 3,723,03S discloses a machine and an improved method of packaging a 5 hot melt adhesive. This produces an er.d product known as pillows in the industry. These pillows can be coextruded with a non-tacky polymer such as polyethylene for producing pressure sensitive adhesives that are non-tacky at room ternperature. This coextrusion coating prevents the pillows from blocking together in a solid mass at room temperature.This as well as other packaging methods discussed above produce hot melt adhesives in 10 non-tacky packages. However, once the coextruded pillows, as well as others are melted for use on an application line, the hot melt composition returns to being tacky again.
The key to all of the above methods, is that the packaging film or detackifying means are compatible with the adhesive so as to not change the resu~ting physical characteristic of the adhesive. Thus, the adhesive remains tacky at room temperature after the adhesive and its 15 package have been melted together.
The present invention is novel and different from all of the above disclosures in that it utilizes a pelletizing aid to change the physical characteristics of the hot melt pressure sensitive compositions to allow for their use in other applications such as injection molding. The compositions can be used to produce non-tacky articles by injection molding. The present 20 invention therefore allows the use of pressure sensitive hot melt compositions in applications other than adhesives.

Summary Of The Inven~ion The present invention discloses a polymeric composition in pellet forrn comprising:
I. From about 97 par~s to about 99.9 parts by weight of a tacky hot melt composltlon comprislng:
a) from about 2.0 to about 20 percent by weight of a high molecular weight block copolymer having the general configuration A-B-A and a molecular weight greater than about 200,000;
b) up to about 30 percent by weight of at least one compatible block copolymer;
and c) from about 20 to about 98 percent by weight of a compatible viscosity modifier;
and II. from about 0.1 to about 3.0 percent by weight of a pelletizing aid.
These resultant compositions are further characterized by a viscosity of greater than about 500 cps at 1 77C, specific gravity of greater than about 0.8, and Mettler Softening Points of greater than about 90C. The pellets thus formed are soft, non-blocking, substantially without surface tack, and exhibit an elastic rebound, as characteriæd by G' (elastic or storage modules) measurements. These pellets are suitable for use in molding, especially injection molding. Any molded products produced therefrom also retain the substantially surface tack free properties.
The pellets can be made into any convenient sizes. Preferably, the pellets are substantially spherical, with sizes ranging from about 1/8 to about 3/8 inch (3mm to 10mm) in diarneter for easy handling. The pellets can also be ellipsoidal and cylindrical. The preferred dimensions for these shapes can range from about 3mm by 10mm to about 10mm by 20mm. While the rest of the composition deterrnines the overall bulk properties of the pellets and articles molded therefrom, the pelletizing aid determines the surface properties of not only the pellets, but the articles made from such pellets.
The present invention further discloses articles molded from polymeric compositions in pellet form comprising:
a) a tacky hot melt composition comprising;
1 ) at least one high moiecular weight triblock copolymer of the general configuration A-B-A; and 2) a plasticizer; and b) a pelletizing aid, 25 wherein said pelletizing aid substantially surrounds the tacky composition such that the molded articles are soft, non-blocking and substantially without surface tack. Optionally, other polymers such as diblock or other triblocks can be added.
Injection molded articles produced from such compositions can include shoe soles, drum pads, toys, therapeutic hand exercising grips, shock absorbers, acoustical insulators, `-- 216437~

synthetic skin, masks, chair pads and so on. These compositions have potential for use in any article that can be injection molded, and is not limited to injection molded articles.
The present invention also discloses an under-water pelletizing process, utilizing a pelletizing aid to produce pellets that are substantially free of surface tack, soft and non-5 blocking. The process varies slightly for each product depending on the plasticizer loading,and comprises the steps of:
a) blending the hot melt components to form a substantially homogenious hot melt mixture;
b) forcing said substantially homogeneous hot melt mixture through a die for forming substantially homogeneous hot melt ribbons and forming resultant pellets therefrom;
c) solidifying said pellets by use of a cooling medium;
d) applying said pelletizing aid.

Detailed Descriptions The polymeric composition of the present invention comprises a high molecular weight triblock copolymer. This copolymer presents in amounts of about 2 to about 20 percent by weight, preferably from about S to about 20 percent by weight, ar d is a subst~ntially linear A-B-A block copolymer having a molecular weight in excess of about 200,000 as measured by Gel Permeation Chromatography, with values reported relative to polystyrene standards, wherein said A block can be polystyrene and said B block can be ethylene-butylene, ethylene-propylene, or mixtures thereof. Polymers of this type, such as Kraton G- 1651, are of substantially h~gher molecular weight than conventional S-EB-S block copolymers generally used in the hot melt adhesive industry.
A compatible A-B-A triblock copolymer, A-B diblock copolymer, and A-B-A-B-A-B
multiblock copolymer, radial block copolymer, and grafted versions of such copolymers can also be present and include Shell Chemical's TKG-IOI and RP-6912, and A-B-A block copolymers as disclosed in Collins et al., U.S. Pat. No. 4,136,699 or available under the tradename of Kraton G- 1650 commercially available from Shell Corporation. Smallconceht-ations of less than about 4 percent of Kraton G- 1651 may also be blended with other polymers such as EVA and EMA as well as crystalline and amorphous polyolefins if onc 21~4376 desires to reduce the viscosity and improve processability of the composition and/or increase the tack for some applications.
The plasticizer is broadly defined as a typically organic composition that can be added to thermoplastics, rubbers, and other resins to improve extrudability, flexibility, workability or 5 stretchability and is chosen in such a way that the resultant softness and tack-free characteristics of both the pellets and the subsequently produced articles are met. Fluid or liquid plasticizers are preferred. Such fluid ingredient may be provided as a liquid resin, a liquid elastomer, or any other material which flows at ambient temperatures and is compatible with the block copolymer.
The plasticizers useful herein are those selected from the group consisting of mineral or petroleum based hydrocarbon oils, polybutene, liquid tackifying resins, liquid elastomers, or functionalized oils such as glyceryl trihydroxyoleate or other fatty oils. The oils used are primarily hydrocarbon oils and are low in aromatic content and are paraffinic or naphthelnic in character. The oils are preferably low in volatility, are transparent, or have minim~l color and 15 odor. The use of plasticizers in this invention also contemplates the use of olefin oligomers, low molecular weight polymers, vegetable oils and their derivatives and similar plasticizing liquids. These plasticizers are useful in amounts up to about 98 percent by weight, preferably up to about 90 percent.
The pelletizing aid is selected from the group consisting of polyethylene, modified 20 polyethylene, polyamide or steararnide waxes. Many other waxes or other pelletizing aids not on this list could also be useful provided the resultant softness and tack-free properties are met.
The pelletizing aid is capable of substantially surrounding the pellet and the surface of the articles formed remained non-tacky. Preferred waxes are Acrawax CTM stearamide wax available from Lonza, Inc. in Fairlawn, NJ, Castor hydroxy waxes and ParicinTM hydroxyamide 25 waxes available from Caschem in Bayonne, NJ, Neptune 968T~ available from Shamrock Technologies in Newark, NJ, Shamrock S-395 rM polyethylene wax available from Shamrock Technologies in Newark, NJ, Hoechst Wax PED 1217~ modified polyethylene available from Hoechst Celanese in Somerville, NJ. More preferably, these pelletizing aids are polyethylene waxes and come in powder form.

216~376 The pellelizing aid is present in small amounts compared to the total hot melt composition. It is present from about 0.1 to about 3 percent by weight, preferably from about 0.1 to about I percent by weight. This amount is substantially less or comparable to the packaging film of prior art packaging methods.
S As discussed above, the pellets thus formed are soR, non-blocking, substantially without surface tack and exhibit an elastic rebound. rhis last characteristic can be measured by the elastic or storage modulus (G'). The higher the modulus, the more likely for the material to go back to its original shape. Depending on the applications, the preferred amounts of the triblock copolymers used can vary. At lower loadings of the high molecular weight triblock copolymer, the pellets forrned resemble gels. They possess some elastic rebound, but tend to retain same physical property over a wide-temperature range, or over a long time frame. These pellets are desirable for making articles such as Santa Claus' bellies. At higher loadings of this copolymer, the pellets formed have high elastic modulus and hence, tend to return to their original shape faster. They are more suited for producing articles such as drum pads.
Compatible polymers or copolymers discussed above can also be added to modify the properties of the pellets. These are generally of low molecular weight, and pellets made with an amount of the high molecular weight triblock copolymer tend to have more rebound than those made with the same amount of a blend of this copolymer and the low molecular weight compatible polymer or copolymer. These compatible polymers or copolymers are thus added for customizing the final applications or uses.
These pellets are suitable for use in molding, especially injection molding. Thecomposition suitable for such processes comprises:
a) a tacky hot melt composition comprising;
I) at least one high molecular weight triblock copolymer of the general configuration A-B-A; and 2) a plasticiær; and b) a pelletizing aid;
wherein said pelletizing aid substantially surrounds the tacky composition such that the molded articles are soft, non-blocking and substantially without surface tack. Optionally, other-polymers such as diblock or other triblocks can be added. Preferably, the tacky hot melt composition comprises from about 97 to 99.9 percent by weight of the article, more preferably from about 99 to 99.9 percent by weight.
Any molded articles produced therefrom also retain the substantially surface tack-free 5 properties and rebound. Such articles can include drum pads useful as acoustical pads for vibration damping, disc players, ear phones, percussion surfaces on electronic drum kits and so on; soles, shoe insoles, in-line skate soles and so on; pads for use in athletic gear such as mouth pads, protective guards, encapsulants for other solid protective pads and so on; bicycle seats, gloves, bicycle shorts and so on; medical equipments such as pads for wheel chairs, 10 donut-shaped pads for seats and so on; furniture pads such as mattress pads, chair pads and so on; special effects articles such as body parts, Santa Claus belly, and others that are useful in movies. Unlike the prior art, the pelletizing aid used herein blooms to the surface during the molding process, such that it substantially completely surrounds the tacky composition below and produces ar~icles substantially free of surface tack when cooled. Tl~s is surprising 15 because the amount of pelletizing aid used in the formu~ation is small, and according to prior art teachings, should not substantially interfere with the properties of the bulk composition, nor should it change the surface properties.
The present invention further discloses a method for making such pellets. The manufacturing process can vary slightly for each product depending on the plasticizer 20 loading. The current process requires multiple passes through a co-rotating twin screw with the product being pelletized at the end of each pass and then refed into the extruder for the further addition of plasticizer. The 90 percent plasticizer materials require three passes, while lower plasticizer loadings may only require two passes. It is important to note that the materials are pelletized with the pelletizing aid after both passes. llle concentration of the 25 pelletizing aid in the water can range from about 0.1 percent to about 3 percent by weight, preferably about 0.1 to about lwt percent based on anticipated production rate for each pass. A
specific, preferred manufacturing process comprises:
a) blending the hot melt components to form a substantially homogeneous hot melt mixture;

_- 2164376 b) forcing said substantially homogeneous hot melt mixture through a die having a series of voids in a circular pattern to form a series of substantially homogeneous hot melt ribbons;
c) further forcing said homogeneous hot melt ribbons past rotating blades in substantially parallel position to said die, cutting said substantially homogeneous hot melt ribbons to forrn resultant pellets;
d) substantially solidifying said pellets by use of a liquid cooling mediurn said liquid cooling medium containing a pelletizing aid, being circulated past said die and rotating blades on the side where said substantially homogeneous hot melt ribbons emerge;
e) transporting said hot melt pellets to a drying area;
f) substantially removing liquid from said hot melt pellets by blowing.
As depicted above, the pelletizing aid is present in the cooling medium. It can also be added to the hot melt composition prior to blending or during the pelletizing steps by co-feeding a solution of pelletizing aid with the hot melt composition.
It is well known in the art that stabili~ers or antioxidants can also be used in the compositions to protect against heat or light induced degradation. These compounds are added to the compositions in small arnounts, are inert, and therefore have no effect on the other physical properties of the compositions. Other compounds that could be added that also do not effect physical properties are pigments for color, fluorescing agents, and any compounds that mask odor. Additives such as these are known to one of skill in the art.
This invention is further illustrated by the following non-limiting examples.

F~amples Test Methods 1. Melt Viscosities The melt viscosities of the hot melt adhesives were deterrnined on a Brookfield Thennosel Viscometer Model DV-II+. The viscosities are reported in centipoise.
(rnPascc) 30 2. S~ecific GraYitY

-- ~16437b The specific gravity was determined using test method ASTM D792 with isopropyl alcohol as the liquid.

3. Mettler SoRenin~ Point The Mettler softening points are deterrnined using test method ASTM D3461.
5 4. nyn~rnic Temperatllre Steps Storage modulus (G') and Tg were determined using a Rheometrics Scientific Dynamic Mechanical Spectrometer Model #RDS7700. The parallel plates used had a 25 mm diameter and a 1.502 mm gap. The instrument was set to a frequency of 10 rads/sec and temperature sweep was performed from 180C to -50C.
10 5. Rloom Gelometer Rigidity of the samples was determined using a Precision Bloom Gelometer CatalogNo. 68705.

E~amples 1~:
The following adhesive formulations are provided for illustrative purposes only.These examples illustrate the physical properties achieved with these types of hot melt compositions but there are many more compositions with differing physical characteristics.
These compositions are listed in Table 1.
The dynamic properties (G') were measured as described above and are shown in figure 20 1. The higher the G' value, the more elastic character, and hence t'ne higher tendency to return to its original shape. These were also tested for other properties and the measurements are shown in Table 2.

- 21~376 Table I
Composition By Weight Percent F~ample 1 ~ ~ 4 Kraton G1651 10.0 5.0 7.0 7.0 Kraton G1650 -- 5.0 12.0 17.0 Kaydol Oil 89.5 89.5 80.0 75.0 * Antioxidant 0.1 0.1 1.0 o.5 ** W Absorber 0.4 0.4 -- o.5 *** Pigment -- Minute Amount Minute Arnount About 0.1% Shamrock S-395 Pelletizing aid was added to each of the compositions.* Either Irganox 1076 antioxidant or Irganox 1010 antioxid~nt or a blend of the two may be used.
** A blend of approximately half Tinuvin 770 and half Tinuvin 328 was u~ed.
*** Minute arnounts of either Sudan Blue 670, Sudan Orange 220, or Sudan Yellow 146 or blends thereof may be used.

Table 2 Physical Characteristics E~ample 1 2 3 4 Method Used Specific ASTM D792 0.86 0.85 0.86 0.86 Gravity Density (#/gal) " 7.1 7.1 7.1 7.2 Viscosity ,~ 143,250 cp 1,700 cp Viscosity ~ 21,625 cp 770 cp Viscosity ,~ 4,350 cp 190 cp Viscosity ~ 1,060 cp 60 cp Mettler ASTM D3461 282.8 + 2.9 255.8 _ 0.3 SoRening Pt ~) G' at 300F RDS - Parallel 2.64E+04 3.29E+03 4.24E+03 4.18E+04 Plates G' at 200F Frequency =1 4.76E+04 1.97E+04 5.1 IE+04 2.1 lE+05 O rad/s G' at 77F Initial Temp = 4.27E+04 3.12E+04 1.71E+05 5.14E+05 Tg (upper) - " 97.9 (208.2) 104.9 (220.8) C (F) Tg(lower)- " -58.1 (-72.6) -SS.S (-67.9) -54.3 (-65.7) -56.9 (-70.4) C ~F)

Claims

1. A polymeric composition in pellet form comprising:
1. A tacky hot melt composition comprising:
a. from about 2 to about 20 percent by weight of a high molecular weight block copolymer having the general configuration A-B-A- and a molecular weight greater than about 200,000;
b. up to about 30 percent by weight of at least one compatible block copolymer; and c. from about 20 and to about 98 percent by weight of a compatible plasticizer; and II. From about 0.1 to about 3 percent by weight of a pelletizing aid.

2. The composition of Claim 1 wherein the pelletizing aid substantially surrounds the tacky hot melt composition to form a pellet that is substantially free of surface tack.

3. The composition of Claim 1 wherein said plasticizer is selected from the group 15 consisting of naphthelenic oil, paraffinic oil, liquid elastomers, liquid tackifiers, polybutene, and mixtures thereof.

4. The composition of Claim 1 wherein said B block is selected from the group consisting of ethylene-propylene, ethylene-butylene, and mixtures thereof.

5. The composition of Claim 1 wherein said A block is polystyrene.

6. The composition of Claim 1 wherein said pelletizing aid is selected from the group consisting of polyethylene, modified polyethylene, polyamide, or stearamide waxes.

7. The composition of Claim 1 wherein said pelletizing aid is a polyethylene wax.

8. The composition of Claim 1 wherein said pelletizing aid is in powder form.

9. The pellets of Claim 1 wherein said pellets comprises shapes selected from the group consisting of substantially spherical, elliptical and cylindrical.

10. A hot melt composition in pellet form comprising a blend of from about 5 to about 15 percent by weight of a high molecular weight block copolymer having the general configuration A-B-A, said block copolymer having polystyrene end blocks and a molecular weight greater than about 200,000; at least one compatible block copolymer of less than about 30 percent by weight selected from the group consisting of an A-B

diblock, an A-B-A-B-A-B multi block, an A-B-A triblock, a radial block and grafted versions thereof; from about 50 and about 95 percent by weight of a compatible plasticizer; and from about 0.1 to about 1.0 percent by weight of a pelletizing aid comprising a polyethylene wax.

11. A hot melt composition of Claim 9 wherein said compatible block copolymer is present from about 5 to about 20 percent by weight.

12. A method for pelletizing the hot melt composition of Claim 1 comprising the steps of:
a. blending the hot melt components to form a substantially homogeneous hot melt mixture;
b. forcing said substantially homogeneous hot melt mixture through a die for forming substantially homogeneous hot melt ribbons and forming resultant pellets therefrom;
c. solidifying said pellets by use of a cooling medium;
d. applying said pelletizing aid.

13. The method of Claim 12 wherein said pelletizing aid is selected from the group consisting of polyethylene, modified polyethylene, polyamide, or stearamide waxes.

14. The method of Claim 12 wherein said pelletizing aid is a polyethylene wax.

15. The method of Claim 12 wherein said blending step is carried out by means of a twin screw extruder.

16. The method of Claim 12 wherein the pelletizing aid is introduced in a manner selected from the group consisting of during the blending step, in the cooling medium and after solidification of the pellets.

17. The method of Claim 12 wherein said liquid is removed from said pellets in a manner selected from the group consisting of blowing the pellets, and by means of a moving screen.

18. A method for pelletizing the hot melt composition of Claim 1 comprising:
a. blending the hot melt components to form a substantially homogeneous hot melt mixture;
b. forcing said substantially homogeneous hot melt mixture through a die having a series of voids in a circular pattern to form a series of substantially homogeneous hot melt ribbons;
c. further forcing said homogeneous hot melt ribbons past rotating blades in substantially parallel position to said die to form resultant pellets;
d. substantially solidifying said pellets by use of a liquid cooling medium containing a pelletizing aid, said cooling medium being circulated past said dieand rotating blades on the side where said substantially homogeneous hot melt ribbons emerge.
e. transporting said hot melt pellets to a drying area;
f. substantially removing liquid from said hot melt pellets by blowing.

19. An article molded from a polymeric composition in pellet form comprising:
a) a tacky hot melt composition comprising;
1) at least one high molecular weight triblock copolymer of the general configuration A-B-A; and 2) a plasticizer; and b) a pelletizing aid, wherein said pelletizing aid substantially surrounds the tacky composition such that the molded articles are soft, non-blocking and substantially without surface tack.

20. An article according to Claim 19 wherein said pelletizing aid is present in an amount from about 0.1 to about 1 percent by weight.

21. Molded articles such as drum pads, soles, therapeutic hand exercising grips, shock absorbers, acoustical insulators, pads for athletic gear, pads for medical equipment, furniture pads and special effects articles comprising the compositions of Claim 1 wherein said articles are substantially without surface tack.

22. Molded articles such as drum pads, soles, therapeutic hand exercising grips, shock absorbers, acoustical insulators, pads for athletic gear, pads for medical equipment, furniture pads and special effects articles comprising the composition of Claim 9 wherein said articles are substantially free from surface tack.