Abstract:
The present invention is directed to pressure sensitive hydrocolloid adhesive compositions having probe tack of about 300-750 grams force, tensile strength of about 500-3500 grams/cm 2  and saline absorbency of about 500-5000 grams/m 2 /24 hours.

Description:
This Appln claims benefit of Provisional No. 60/106,799 filed Nov. 3, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to pressure sensitive adhesive compositions and more particularly to pressure sensitive hydrocolloid adhesive compositions suited for use in ostomy, wound and incontinence care. 
     The compositions of this invention can be used for example to hold ostomy or incontinence devices onto the body of the user or to hold wound dressings in position for treating skin ailments or as the wound dressing itself. 
     Various hydrocolloid adhesive compositions suitable for medical uses are disclosed in the patent literature, e.g., U.S. Pat. No. 3,339,549 (Chen); U.S. Pat. No. 4,192,785 (Chen, et al.); U.S. Pat. No. 4,166,051 (Cilento, et al.); U.S. Pat. No. 4,393,080 (Pawelchak, et al.); U.S. Pat. No. 3,612,053 (Pratt, et al.); U.S. Pat. No. 4,231,369 (Sorensen, et al.); U.S. Pat. No. 3,908,658 (Marsan); U.S. Pat. No. 4,367,732 (Poulsen, et al.); U.S. Pat. No. 4,378,018 (Alexander, et al.); and U.S. Pat. No. 4,393,150 (Krones). 
     Hydrocolloid adhesives are composed of powdered hydrocolloids dispersed in an elastomeric polymer matrix. They have been found to make excellent pressure sensitive adhesives for attachment of devices to the skin. Useful hydrocolloid adhesives depend on their initial tack, cohesive strength, and absorbency to achieve wearing times on skin of up to 10 days or longer. It is also required that components of hydrocolloid adhesives be cost effective, easy to process, and compatible with other device components. 
     OBJECT OF THE INVENTION 
     It is an object of the present invention to provide a biocompatible hydrocolloid adhesive composition simultaneously having preferred probe tack, tensile strength and saline absorbency as provided in Table I. 
     
       
         
               
               
               
             
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Characteristic 
                 Usefulness Range 
                 Preferred Range 
               
               
                   
               
             
             
               
                 Probe Tack 
                 About 300-750 
                 About 500-650 grams, force 
               
               
                   
                 grams, force 
               
             
          
           
               
                 Tensile 
                 About 500-3500 
                 About 1500-2500 
                 About 500-1500 
               
               
                 Strength 
                 grams/cm{circumflex over ( )}2 
                 g/cm{circumflex over ( )}2 extruded 
                 non-extruded 
               
               
                 Saline 
                 About 500-5000 
                 About 2000-3500 
                 About 1500-2500 
               
               
                 Absorbency 
                 g/m{circumflex over ( )}2/day 
                 g/m{circumflex over ( )}2/d extruded 
                 non-extruded 
               
               
                   
               
             
          
         
       
     
     It is also an object of the present invention to provide a biocompatible adhesive that is easy to process, cost efficient, durable and that doesn&#39;t swell excessively when hydrated. 
     It is an object to achieve with the present invention probe tack values above about 300 grams, force, as this value has been found to be desirable for attaining a strong initial bond to the skin. Improved bonds are generally obtained with increased tack, though too strong a bond may damage skin upon removal. 
     It is also an objective of the present invention to achieve acceptable shear-strength and peel properties. It has been determined that tensile strengths of about 500-3500 g/square centimeter are desirable. It is also recognized, however, that decreased flexibility or reduced adhesion may result if cohesive strength is excessive. 
    
    
     DESCRIPTION OF THE INVENTION 
     The adhesive compositions of the present invention utilize a poly(ethylene-propylene) rubber (EPR) having a broad molecular weight, amorphous structure and an ethylene content of 50% or less. The EPR is also a random copolymer and easy to process. The preferred EPR is Vistalon 404, Exxon Chemical Co. Low molecular weight species in the EPR favor bond formation while higher molecular weight species enhance cohesive and peel strength. A compatible tackifying resin for this elastomer preferred for optimum tackification is a low molecular weight, highly hydrogenated polyvinylcyclohexane. Commercially available examples are Regalrez® 1085 or Regalrez® 1094. (Hercules, Inc.). It is further preferred that the polyvinylcyclohexane have a softening point below body temperature and most preferably below room temperature such that it may further improve the wetting of skin by the elastomeric component. A commercially available example is Regalrez® 1018 (Hercules, Inc.). In particular, the use of low softening point resin allows for increasing the concentration of tackifier by a corresponding reduction in the concentration of plasticizing components. Both factors favorably influence adhesion, while retaining flexibility that may be lost when resins of higher softening point are employed. Adhesion is easily measured by using a task test to determine the bond forming capability. 
     Because hydrocolloid adhesives are composed of an elastomeric phase and a hydrocolloid phase, proper optimization of the adhesive formulation requires simultaneous optimization of the individual phases. While some interaction does occur between phases, the elastomeric phase is primarily responsible for the adhesive and cohesive strength properties, and the hydrocolloid phase is primarily responsible for the overall moisture handling and moisture interaction characteristics of the formulation. Adhesion and cohesion typically represent a balance of competing behaviors, and strong elastomers may not yield very effective adhesives. Moisture handling is more than just absorption, per se, but must be thought of in terms of absorption rate, absorption capacity, and the properties of the hydrated material. The hydrocolloid phase is key in determining these characteristics. 
     The ability of the adhesive to form a bond to the skin is directly related to the probe tack of the adhesive. Tack is generated by the action of tackifying resins to enhance wetting of the skin by the elastomeric components of the formulation. Modification of elastomers by tackifiers enables elastomers to form bonds while retaining their cohesiveness and contribute strength to the overall formulation. Compatibility of the tackifier with the elastomer is believed to be a key factor in tackifier effectiveness, as is the presence of low molecular weight species in the elastomer. Typically, the elastomer is blended with a styrenic block copolymer for optimum cohesive strength. 
     In order to attain adhesion to the skin for more than 1 or 2 days, it is necessary that the adhesive absorb fluid at a rate greater than or equal to the rate of transepidermal water loss (TEWL), approximately 7-10 g/square meter per hour on average. The actual absorption rate required to maintain skin adhesion can in practice be somewhat greater than this value as a function of weather, physical activity, etc. To obtain the minimum absorption capacity, this absorption rate should be multiplied over the wearing time. 
     Absorption by the adhesive is necessary to effectively manage perspiration from the skin. Without this capability, the adhesive would fail after short wearing times, and skin condition would be adversely affected. However, absorption also causes degradation of the adhesive component resulting from hydration and chemical attack by stomal discharge. This degradation occurs because the absorbent hydrocolloids act regardless of the source of the fluid absorbed, either perspiration or stoma effluent. Therefore, limiting absorption to the minimum necessary to manage perspiration will limit how stoma fluid will impact dressing integrity. 
     Denture adhesives are an example of water activated adhesives. Typically, sodium carboxy-methyl cellulose (NaCMC) is used as a component of these formulations. A blend of NaCMC grades is used to achieve desired properties. Differences between grades are defined by the degree of substitution (DS) of carboxymethyl groups onto the anhydroglucose repeat units of the cellulose chain. Higher DS grades (&gt;1.0) are used to impart a high rate of absorption, while lower to moderate DS grades (&lt;1.0) are included for their long term cohesiveness. One further requirement of the formulation is that its response to moisture must not compromise the performance of the device for which the adhesive was intended. As hydrocolloid adhesives absorb moisture they begin to swell. The hydrating hydrocolloid powders transform the rubbery elastomer phase into a more gelatinous composition that appears to grow. Typically this growth occurs in the direction of a free surface. For wound dressings the growth is into the wound. For ostomy skin barriers the growth is toward the stoma, and is called turtlenecking for its resemblance to the collar on a turtleneck sweater. 
     In some cases turtlenecking is desirable, as it has been reported to provide an effective seal around the stoma itself and prevents leakage of stomal effluent and undermining of the skin barrier. However, excessive amounts of turtlenecking can have the opposite effect, causing effluent to be diverted from the pouch and against the skin. Excessive turtlenecking in hydrocolloid adhesives can be avoided by limiting elongation of the elastomeric phase during hydration. Key factors in attaining acceptable turtlenecking are the choice of elastomer, the balance of absorption rate and capacity within the limits described above, the balance of cohesive and adhesive properties in the elastomer phase. 
     In contrast to denture adhesives, it has been discovered that use of higher DS CMC grades in combination with low to moderate DS grades reduces the rate of moisture absorption in hydrocolloid adhesives. In other words, as the average degree of substitution of the CMC in the formulation increases, the absorption rate of the hydrocolloid adhesive decreases. Further, overall absorption capacity increases. As a result, longer wearing times are possible because the influence of stomal effluent on adhesive integrity is reduced, though the film forming and water activated bonding capabilities of CMC are retained. Additionally, turtlenecking characteristics are favorably impacted. 
     Although it is possible to lower the absorption rate of the formulation by using different hydrocolloids having a weaker affinity for water, the impact on overall adhesive properties is not as favorable as with the use of higher DS CMC. Examples 34 and 35 below show how use of pregelatinized starch, a low absorbing hydrocolloid, reduces the absorption rate of the formulation. However, in contrast with the performance of high DS CMC, the overall absorption capacity of the adhesive is not increased. Further, the water activated bonding power of hydrated starch to human skin is not believed to be as effective as either pectin or especially CMC. Therefore, addition of a minor amount of starch, or other low absorbing hydrocolloids, may expand the useful range of this invention to the extent that the effectiveness of the preferred hydrocolloids in extending wear time is not compromised. 
     Addition of a small amount of a powdered cellulose, which is not a hydrocolloid but a water swellable powder, is also useful for reducing moisture absorption while still being of similar composition to NaCMC. A further benefit of adding powdered cellulose is that it improves cohesive strength of the overall formulation. 
     As a result of the fact that the EPR is can be readily blended with the other formulation components, a variety of conventional compounding processes are believed to be suitable for obtaining a homogeneous mixture. Potential mixing processes would include solvent blending, continuous or semi-continuous compounding, calendering or milling, and internal or external mixers. The preferred mixing process utilizes a high intensity batch mixer, which has been heated to between 250 and 330° F. The process proceeds by alternating additions of rubber or block copolymer with any of the powders and one of the low molecular weight components, which are mixed in groups until homogeneous. The entire process proceeds for as long as about 90 minutes or more. The low molecular weight components include any of the tackifiers and the plasticizer. The plasticizer used should be a low molecular weight polymer appropriately chosen to reduce the modulus of the formulation, promote flexibility and conformability of the adhesive, and be suitable for contact with the skin or mucosal tissue. Preferably petrolatum may be used. 
     Formulated adhesive mass may then be formed by any of various means into smooth sheets. The preferred forming methods are extrusion or compression. A useful thickness range for the adhesive is believed to be in the range between 0.005 inch and 0.25 inch. This adhesive sheet may be laminated with a wide variety of films, foams, non-woven or other fabrics, etc. and also to paper, some of which may have been coated with release agents to promote removal. The adhesive sheet may be cut into useful sizes, shapes and dimensions including discs, profiles, contours or other constructions of adhesive articles. Laminates may be added readily to the adhesive when it is maintained at elevated temperature. Preferred methods of lamination include a roll based lamination station or a compression type process. Cutting may be accomplished using several methods, the preferred ones being a rotary cutting die or a platen type cutting die. 
     EXAMPLES 
     Table 2 provides a listing of 25 hydrocolloid adhesives pursuant to the present invention. Each of these compositions are blended to produce compositions with the characteristics listed in Table 2A within the usefulness ranges of Table 1. 
     Additional examples showing the utility of the invention are shown in Table 6. 
     Examples of the trade names for components of the compositions are the following: 
     ethylene propylene rubber—Vistalon 404, Exxon Chemical Co.; 
     styrenic block copolymer—Kraton D1107, Shell Chemical Co.; 
     tackifier (solid)— Piccotac 95, Hercules, Inc.; 
     tackifier (liquid)— Regalrez 1018, Hercules, Inc.; 
     NaCMC—Sodium Carboxymethyle cellulose FCC grade with 
     DS7=degree of substitution=0.7 
     DS12=degree of substitution=1.2 
     pectin—Pectin, USP 100; 
     powdered cellulose, FCC—Solka Floc 200 FCC, Fiber Sales &amp; Development Corp. 
     Antioxidant—Irganox 1010, Ciba Geigy Corp.; 
     Plasticizer—white petrolatum, USP; 
     Cyclo-aliphatic tackifying resin—Relarez 1094, Hercules, Inc.; 
     Hydrogenated rosin ester—Pentalyn H., Hercules, Inc.; 
     Pregelatinized starch—Prejel PA5, Avebe, Inc. 
     Examples 1-4 and 17-20 of Tables 2 and 2A demonstrate acceptable performance within the usefulness ranges of Table 1. These examples represent a base adhesive which has no liquid tackifier, high DS DMC, or powdered cellulose but still achieves useful properties. Improvements to probe tack resulting from the use of low softening point tackifier are shown in Table 3. The effectiveness of high degree of substitution sodium carboxymethyl cellulose to reduce absorption is shown in Table 5. The ability of powdered cellulose to reduce absorption and increase strength is demonstrated in Table 4. 
     Measurements of probe tack were based on the method described in ASTM D2979 using an inverted probe machine. In this test, conducted at room temperature, the dwell time was 1 second, and the approach speed was 1 cm/second. Tensile measurements were based on ASTM test method D412 with the crosshead speed set to 200 mm/minute using a dumb bell shaped test specimen. The peak tensile strength is reported. Absorbency measurements were conducted based on the British Pharmacopoeia method wherein a flat adhesive specimen of known weight and area is exposed to 0.9% saline solution. The exposed adhesive is incubated at body temperature for 24 hours and re-weighed. The weight difference per area is reported. 
     
       
         
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                   
                   
                   
                   
                   
                   
                   
                 Low 
                   
                   
                   
               
               
                   
                 Ethylene- 
                 Styrenic 
                   
                   
                   
                   
                 Softening 
               
               
                   
                 Propylene 
                 Block 
                 Tackifying 
                 Anti- 
                 NaCMC 
                   
                 Point 
                   
                 NaCMC 
                 Powdered 
               
               
                 Example 
                 Rubber 
                 Copolymer 
                 Resin 
                 oxidant 
                 DS7 
                 Pectin 
                 Tackifier 
                 Plasticizer 
                 DS12 
                 Cellulose 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 33.0% 
                 10.0% 
                   
                 9.5% 
                   
                   
               
               
                 2 
                 2.0% 
                 10.0% 
                 33.0% 
                 0.5% 
                 27.0% 
                 20.0% 
                   
                 7.5% 
               
               
                 3 
                 10.0% 
                 16.0% 
                 24.0% 
                 0.5% 
                 32.5% 
                 5.0% 
                   
                 12.0% 
               
               
                 4 
                 7.0% 
                 10.5% 
                 28.0% 
                 0.5% 
                 26.0% 
                 20.0% 
                   
                 8.0% 
               
               
                 5 
                 6.0% 
                 13.0% 
                 30.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                   
                 8.5% 
               
               
                 6 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 2.0% 
                 8.5% 
               
               
                 7 
                 6.0% 
                 13.0% 
                 25.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 5.0% 
                 8.5% 
               
               
                 8 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 5.0% 
                 5.5% 
               
               
                 9 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 30.0% 
                 7.0% 
                 5.0% 
                 5.5% 
                 5.0% 
               
               
                 10 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 20.0% 
                 7.0% 
                 5.5% 
                 5.5% 
                 15.0% 
               
               
                 11 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 10.0% 
                 7.0% 
                 5.5% 
                 5.5% 
                 25.0% 
               
               
                 12 
                 6.0% 
                 13.0% 
                 25.0% 
                 0.5% 
                 15.0% 
                 15.0% 
                 5.5% 
                 5.0% 
                 15.0% 
               
               
                 13 
                 5.0% 
                 12.5% 
                 25.0% 
                 0.5% 
                 28.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 5.0% 
               
               
                 14 
                 5.0% 
                 12.5% 
                 25.0% 
                 0.5% 
                 25.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 5.0% 
                 3.0% 
               
               
                 15 
                 5.0% 
                 12.5% 
                 25.0% 
                 0.5% 
                 22.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 5.0% 
                 6.0% 
               
               
                 16 
                 5.0% 
                 12.5% 
                 28.0% 
                 0.5% 
                 20.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 8.0% 
                 2.0% 
               
               
                 17 
                 5.0% 
                 12.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                   
                 9.0% 
               
               
                 18 
                 2.0% 
                 15.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                   
                 9.0% 
               
               
                 19 
                 8.0% 
                 9.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                   
                 9.0% 
               
               
                 20 
                 5.0% 
                 12.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                   
                 9.0% 
               
               
                 21 
                 5.0% 
                 12.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                 3.0% 
                 6.0% 
               
               
                 22 
                 2.0% 
                 15.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                 6.0% 
                 3.0% 
               
               
                 23 
                 8.0% 
                 9.5% 
                 25.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                 3.0% 
                 9.0% 
               
               
                 24 
                 8.0% 
                 9.5% 
                 25.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                 6.0% 
                 6.0% 
               
               
                 25 
                 8.0% 
                 9.5% 
                 28.0% 
                 0.5% 
                 20.0% 
                 15.0% 
                 3.0% 
                 6.0% 
                 10.0% 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
               
             
           
               
                   
                 TABLE 2A 
               
               
                   
                   
               
               
                   
                   
                   
                 Tensile 
                 24 Hr Saline 
               
               
                   
                   
                   
                 Strength 
                 Absorption 
               
               
                   
                   
                 Probe Tack 
                 g/cm{circumflex over ( )}2 
                 g/sq.m/24 hr 
               
               
                   
                 Example 
                 g tack force 
                 (non-extruded) 
                 (non-extruded) 
               
               
                   
                   
               
             
             
               
                   
                  1 
                 432 
                  852 
                 1937 
               
               
                   
                  2 
                 411 
                 2966 
                 3459 
               
               
                   
                  3 
                 470 
                  860 
                 1439 
               
               
                   
                  4 
                 418 
                 1465 
                 2936 
               
               
                   
                  5 
                 559 
                 1690 
                 2111 
               
               
                   
                  6 
                 481 
                 1451 
                 2479 
               
               
                   
                  7 
                 517 
                 1637 
                 2947 
               
               
                   
                  8 
                 615 
                 1690 
                 3507 
               
               
                   
                  9 
                 586 
                 1587 
                 2859 
               
               
                   
                 10 
                 418 
                 1574 
                 2113 
               
               
                   
                 11 
                 438 
                 2065 
                 1538 
               
               
                   
                 12 
                 477 
                 1757 
                 2257 
               
               
                   
                 13 
                 572 
                 1032 
                 3590 
               
               
                   
                 14 
                 449 
                 1919 
                 3237 
               
               
                   
                 15 
                 425 
                 1830 
                 2446 
               
               
                   
                 16 
                 599 
                 1312 
                 1869 
               
               
                   
                 17 
                 508 
                  662 
                 2200 
               
               
                   
                 18 
                 426 
                 1538 
                 2705 
               
               
                   
                 19 
                 529 
                  824 
                 3249 
               
               
                   
                 20 
                 491 
                 1205 
                 2209 
               
               
                   
                 21 
                 531 
                  998 
                 2843 
               
               
                   
                 22 
                 420 
                 2183 
                 2861 
               
               
                   
                 23 
                 394 
                  587 
                 2326 
               
               
                   
                 24 
                 450 
                  632 
                 3107 
               
               
                   
                 25 
                 597 
                  873 
                 2426 
               
               
                   
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Examples Showing Improvement in Tack Using Low Softening Point Tackifier 
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                 Low 
                   
                   
                   
                   
               
               
                   
                 Ethylene- 
                 Styrenic 
                   
                   
                   
                   
                 Softening 
               
               
                   
                 Propylene 
                 Block 
                 Tackifying 
                 Anti- 
                 NaCMC 
                   
                 Point 
                   
                 NaCMC 
                 Powdered 
               
               
                   
                 Rubber 
                 Copolymer 
                 Resin 
                 oxidant 
                 Low DS 
                 Pectin 
                 Tackifier 
                 Plasticizer 
                 High DS 
                 Cellulose 
                 Probe Tack 
               
               
                 Example 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 g task force 
               
               
                   
               
             
          
           
               
                 1 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 33.0% 
                 10.0% 
                   
                 9.5% 
                   
                   
                 432 
               
               
                 2 
                 2.0% 
                 10.0% 
                 33.0% 
                 0.5% 
                 27.0% 
                 20.0% 
                   
                 7.5% 
                   
                   
                 411 
               
               
                 3 
                 10.0% 
                 16.0% 
                 24.0% 
                 0.5% 
                 32.5% 
                 5.0% 
                   
                 12.0% 
                   
                   
                 470 
               
               
                 4 
                 7.0% 
                 10.5% 
                 28.0% 
                 0.5% 
                 26.0% 
                 20.0% 
                   
                 8.0% 
                   
                   
                 418 
               
               
                 6 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 2.0% 
                 8.5% 
                   
                   
                 481 
               
               
                 7 
                 6.0% 
                 13.0% 
                 25.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 5.0% 
                 8.5% 
                   
                   
                 517 
               
               
                 8 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 5.0% 
                 5.5% 
                   
                   
                 615 
               
               
                 21 
                 5.0% 
                 12.5% 
                 28.0% 
                 0.5% 
                 30.0% 
                 15.0% 
                 3.0% 
                 6.0% 
                   
                   
                 531 
               
               
                 25 
                 8.0% 
                 9.5% 
                 28.0% 
                 0.5% 
                 20.0% 
                 15.0% 
                 3.0% 
                 6.0% 
                 10.0% 
                   
                 597 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 4 
               
             
             
               
                   
               
               
                 Examples Showing Improvement in Tensile Strength Using Powdered Cellulose 
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                 Low 
                   
                   
                   
                   
               
               
                   
                 Ethylene- 
                 Styrenic 
                   
                   
                   
                   
                 Softening 
               
               
                   
                 Propylene 
                 Block 
                 Tackifying 
                 Anti- 
                 NaCMC 
                   
                 Point 
                   
                 NaCMC 
                 Powdered 
                 Tensile 
               
               
                   
                 Rubber 
                 Copolymer 
                 Resin 
                 oxidant 
                 Low DS 
                 Pectin 
                 Tackifier 
                 Plasticizer 
                 High DS 
                 Cellulose 
                 Strength 
               
               
                 Example 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 g/cm{circumflex over ( )}2 
               
               
                   
               
             
          
           
               
                 13 
                 5.0% 
                 12.5% 
                 25.0% 
                 0.5% 
                 28.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 5.0% 
                   
                 1032 
               
               
                 14 
                 5.0% 
                 12.5% 
                 25.0% 
                 0.5% 
                 25.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 5.0% 
                 3.0% 
                 1919 
               
               
                 15 
                 5.0% 
                 12.5% 
                 25.0% 
                 0.5% 
                 22.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 5.0% 
                 6.0% 
                 1830 
               
               
                 16 
                 5.0% 
                 12.5% 
                 28.0% 
                 0.5% 
                 20.0% 
                 15.0% 
                 2.0% 
                 7.0% 
                 8.0% 
                 2.0% 
                 1312 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 5 
               
             
             
               
                   
               
               
                 Examples Showing Reduced Absorption Using High Degree of Substitution CMC 
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                 Low 
                   
                   
                   
                 24 Hr 
               
               
                   
                 Ethylene- 
                 Styrenic 
                   
                   
                   
                   
                 Softening 
                   
                   
                   
                 Saline 
               
               
                   
                 Propylene 
                 Block 
                 Tackifying 
                 Anti- 
                 NaCMC 
                   
                 Point 
                   
                 NaCMC 
                 Powdered 
                 Absorption 
               
               
                   
                 Rubber 
                 Copolymer 
                 Resin 
                 oxidant 
                 Low DS 
                 Pectin 
                 Tackifier 
                 Plasticizer 
                 High DS 
                 Cellulose 
                 g/sq · m/24 
               
               
                 Example 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 % w/w 
                 hr 
               
               
                   
               
             
          
           
               
                 8 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 35.0% 
                 7.0% 
                 5.0% 
                 5.5% 
                   
                   
                 3507 
               
               
                 9 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 30.0% 
                 7.0% 
                 5.0% 
                 5.5% 
                  5.0% 
                   
                 2859 
               
               
                 10 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 20.0% 
                 7.0% 
                 5.5% 
                 5.5% 
                 15.0% 
                   
                 2113 
               
               
                 11 
                 6.0% 
                 13.0% 
                 28.0% 
                 0.5% 
                 10.0% 
                 7.0% 
                 5.5% 
                 5.5% 
                 25.0% 
                   
                 1538 
               
               
                 12 
                 6.0% 
                 13.0% 
                 25.0% 
                 0.5% 
                 15.0% 
                 15.0% 
                 5.5% 
                 5.0% 
                 15.0% 
                   
                 2257 
               
               
                 25 
                 8.0% 
                 9.5% 
                 28.0% 
                 0.5% 
                 20.0% 
                 15.0% 
                 3.0% 
                 6.0% 
                 10.0% 
                   
                 2426 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 6 
               
               
                   
               
               
                 Additional Formulation Examples Demonstrating the Utility of the Invention 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                 Low 
                   
                   
                   
                   
                 Cyclo- 
               
               
                   
                 Ethylene 
                 Styrenic 
                   
                   
                   
                   
                 Softening 
                   
                   
                   
                 Hydro- 
                 aliphatic 
               
               
                   
                 Propylene 
                 Block 
                 Tackifying 
                 Anti- 
                 NaCMC 
                   
                 Point 
                   
                 NaCMC 
                 Powdered 
                 genated 
                 tackifying 
               
               
                 Example 
                 Rubber 
                 Copolymer 
                 Resin 
                 oxidant 
                 DS7 
                 Pectin 
                 Tackifier 
                 Plasticizer 
                 DS12 
                 Cellulose 
                 Rosin Ester 
                 Resin 
               
               
                   
               
               
                 26 
                 20 
                 2 
                 25 
                 0.5 
                 14 
                 14 
                 5.5 
                 5 
                 14 
               
               
                 27 
                 5 
                 10 
                 30.5 
                 0.5 
                 15.5 
                 30.5 
                   
                 8 
               
               
                 28 
                 5 
                 10 
                 25 
                 0.5 
                 33 
                 17 
                   
                 9.5 
               
               
                 29 
                 5 
                 10 
                 25 
                 0.5 
                 35 
                 12.5 
                   
                 12 
               
               
                 30 
                 5 
                 12.5 
                   
                 0.5 
                 20 
                 15 
                 2 
                 7 
                 8 
                 2 
                 28 
               
               
                 31 
                 13 
                 6 
                   
                 0.5 
                 15 
                 15 
                 5.5 
                 5 
                 15 
                   
                   
                 25 
               
               
                 32 
                 5 
                 12.5 
                 14 
                 0.5 
                 20 
                 15 
                 2 
                 7 
                 8 
                 2 
                   
                 14 
               
               
                  33* 
                 5 
                 12.5 
                 28 
                 0.5 
                 15 
                 15 
                   
                 9 
               
               
                  34* 
                 5 
                 12.5 
                 29 
                 0.5 
                 10 
                 15 
                   
                 8 
               
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                 24 Hr Saline 
               
               
                   
                   
                 Terpene 
                 Pregelatin- 
                 Probe Tack 
                 Tensile Strength 
                 Absorption 
               
               
                   
                 Example 
                 Resin 
                 ized Starch 
                 g tack force 
                 g/cm{circumflex over ( )}2 
                 g/sq · m/24 hr 
               
               
                   
                   
               
               
                   
                 26 
                   
                   
                 504 
                 1714 
                 4788 
               
               
                   
                 27 
                   
                   
                 757 
                 1706 
                 2688 
               
               
                   
                 28 
                   
                   
                 467 
                 — 
                 6006 
               
               
                   
                 29 
                   
                   
                 370 
                 4778 
                 — 
               
               
                   
                 30 
                   
                   
                 644 
                  975 
                 6669 
               
               
                   
                 31 
                   
                   
                 470 
                 1318 
                 3845 
               
               
                   
                 32 
                   
                   
                 409 
                 1673 
                 1985 
               
               
                   
                  33* 
                   
                 15 
                 456 
                 1849 
                 2772 
               
               
                   
                  34* 
                   
                 20 
                 525 
                 2076 
                 2790 
               
               
                   
                   
               
               
                   
                 *Data for examples 33 and 34 is for extruded product.