MXPA01003944A - Blends of polyolefin and poly(ethylene oxide) and process for making the blends. - Google Patents

Abstract

A compositional blend having from about 1 weight percent to about 85 weight percent of a modified polyolefin and from about 99 weight percent to about 15 weight percent of a modified poly(ethylene oxide). The modified polyolefin and modified poly(ethylene oxide) have a total of from about 1 weight percent to about 30 weight percent of a monomer grafted thereto. Included is a method for making the blend comprising using a single pass extruder to perform the steps of melt blending a polyolefin, a poly(ethylene oxide), a polar, vinyl monomer and a sufficient amount free radical initiator to graft from about 1 percent to 100 percent of the monomer onto the polyolefin and poly(ethylene oxide).

Description

MIXES OF POLYOLEPHINE AND POLY (ETHYLENE OXIDE) AND MIXING PROCESS FIELD OF THE INVENTION The present invention relates to mixtures comprising a polyolefin and poly (ethylene oxide) and a method for making the mixtures. In one embodiment, the invention relates to mixtures having up to about 85 percent by weight of a modified polyethylene or a modified polypropylene and a modified poly (ethylene oxide) and a method for making the modified polyolefin and poly blend. (ethylene oxide) modified using a single step reactive extrusion process.

BACKGROUND OF THE INVENTION Personal care products, such as diapers, sanitary napkins, adult incontinence garments, and the like are generally constructed of a number of different components and materials. Such articles typically have a part, usually the backing layer, a liner, or a separator constructed of a liquid repellent film material. This repellent material is appropriately constructed to minimize or prevent the exudation of the liquid absorbed from the article and to obtain a greater utilization of the absorbent capacity of the product. The commonly used liquid repellent film includes plastic materials such as polyethylene films and the like.

Even though such products are relatively cheap, sanitary and easy to use, the disposal of such a product once dirty is not without problems. With greater interest being placed in the protection of the current environment, there is a need to develop materials that are more compatible with existing and existing waste disposal technologies while still delivering performance to what consumers expect. An ideal waste alternative would be the use of municipal sewage treatment and private residential septic systems. The products suitable for disposal in waste systems can be discarded by discharging water into a convenient toilet and are called (disposable with water discharge). Even though the disposal of such items will be convenient, the liquid repellent material that normally does not disintegrate in the water tends to clog the toilets and drainage pipes. It is therefore necessary, even when undesirable, to separate the barrier film material from the absorbent article before discharge with water discharge.

In addition to the article itself, typically the package in which the disposable article is distributed is also made of a water resistant material. Water resistivity is necessary to avoid packing degradation due to environmental conditions and to protect disposable items there. Even when the package can be safely stored with another waste for a commercial disposal, and especially in the case of the packaging of the individual products, it is often more convenient to dispose of the packages in the toilet with the discarded absorbent article. However, in cases where such a package is composed of a water resistant material, it typically results in clogging of the toilet drains.

In an effort to overcome these deficiencies, two methodologies have been used. The first is for hydrophilic materials that are treated with a hydrophobic material to impart the desired water resistance properties to the material.

The second method has been to modify a water resistant polymer. One of the most useful ways to modify polymers involves mixing them with other polymers of different structures and properties. In a few cases, the polymer blend combinations are thermodynamically miscible and exhibit physical and mechanical compatibility. However, by far a large number of mixtures are phase separated and generally exhibit poor mechanical compatibility. The separated phase mixtures can in some chaos exhibit physical and mechanical compatibility where the polymer compositions are similar, for example, the polyolefin mixed with other similar polyolefins, or where the interfacial agents are aggregated to improve the compatibility in the interlayer between the constituents of the polymer mixture.

The polymer blends of polyolefins and poly (ethylene oxide) are melt processable but exhibit very poor mechanical compatibility. This poor mechanical compatibility is manifested in the mechanical property profile of the mixtures in relation to the properties of the unmixed constituents.

In view of the problems of the prior art, it is still highly desirable to provide a material that responds to water. Such mixtures can be used to make disposable barrier films with water discharge, extrusion applications and molded and injected articles.

SYNTHESIS OF THE INVENTION Briefly, one aspect of the present invention provides a modified polyolefin and modified poly (ethylene oxide) blend composition. The blend composition is comprised of from about 1 percent by weight to about 85 percent by weight of a modified polyolefin and from about 99 percent by weight to about 1 percent by weight of a poly (oxide) ethylene) modified. The modified polyolefin and the modified polyethylene oxide have grafted thereto from about 1 percent by weight to about 30 percent by weight, based on the weight of the polyolefin and polyethylene oxide. u monomer.

Another aspect of the invention provides a method for making the modified polyolefin blend composition of modified poly (ethylene oxide). The method provides a single step melt reactive extrusion modification of polyolefin and poly (ethylene oxide). This single pass process provides significant advantages over a stepwise process wherein the polyolefin is first modified by grafting a monomer onto the polyolefin column which is then reextruded with the poly (ethylene oxide). A few of the advantages include cost savings, reduced polymer degradation and greater uniformity in the final product. Specifically, the method of preparing the blend of a modified polyolefin and a modified poly (ethylene oxide) using a single pass melt-through extruder comprises melting the polyolefin and poly (ethylene oxide) into the extruder add to the polyolefin and poly (ethylene oxide) mixture a monomer and a sufficient amount of a free radical initiator to graft from about 1 percent by weight to about 100 percent by weight of the monomer on the polyolefin and the poly (ethylene oxide).

It is an object of the invention to provide a blend composition comprising a modified polyolefin and modified poly (ethylene oxide). More specifically, it is an object of the invention to provide a blend composition comprising a modified polyethylene and a modified polypropylene and modified poly (ethylene oxide).

Another object of the invention is to provide a method for making a modified polyolefin and modified poly (ethylene oxide) blend composition using a single pass reactive extruder.

As used herein, "reactive extrusion" is the use of chemical reactions during the extrusion of the polymer to form the desired products. The free radical initiator, cross-linking agents and other reactive additives can be injected into the extruder to cause such reactions.

DETAILED DESCRIPTION OF THE INVENTION The mechanical and visual compatibility of the polyolefin and poly (ethylene oxide) mixtures is very poor. However, it has unexpectedly been found that the polyolefins and the poly (ethylene oxide) can be modified with one or more monomers, so that materials made from mixtures having upwards of about 85 percent by weight of a polyolefin modified and as little as 15 percent by weight poly (modified ethylene oxide) are responsible for water. More specifically, it has been found that blends of polyolefins and poly (ethylene oxide) when grafted with a polar vinyl monomer during reactive extrusion imparts water response to the films and thermoplastic articles made thereof. So, one aspect of the invention is for a composition of matter comprising a polymer blend having from about 1 weight percent to about 85 weight percent of a modified polyolefin and from about 99 weight percent. weight at about 15 percent by weight of a modified poly (ethylene oxide). Preferably, the blend comprises from about 30 percent by weight to about 85 percent by weight of a modified polyolefin and from about 70 percent by weight to about 15 percent by weight of poly (ethylene oxide) ) modified. More preferably, the mixture comprises from about 55 percent by weight to about 85 percent by weight of a modified polyolefin and from about 45 percent by weight to about 15 percent by weight of poly (ethylene oxide). ethylene) modified.

The amount of monomer added to the mixture of polyolefin and poly (ethylene oxide) may vary. Suggested amounts of monomer range from about 1 percent by weight to about 30 percent by weight, preferably from about 1 percent by weight to about 20 percent by weight, and more preferably, from about from 1 weight percent to about 10 weight percent where all those ranges are based on the total weight of polyolefin and poly (ethylene oxide). Suggested monomers include, but are not limited to polar ethylenically unsaturated monomers and polar vinyl monomers. The desired ethylenically unsaturated polar monomers include 2-hydroxyethyl methacrylate (hereinafter HEMA), poly (ethylene glycol), methacrylates hereafter (PEG-MA), including poly (ethylene glycol) ethyl ether methacrylate, poly (ethylene glycol) ) acrylates, poly (ethylene glycol) ethyl ether acrylate, poly (ethylene glycol) methacrylates with terminal hydroxyl groups, acrylic acid, maleic anhydride, itaconic acid, sodium acrylate, 3-hydroxypropyl methacrylate, acrylamide, glycidyl methacrylate, 2-bromoethyl acrylate , carboxyethyl acrylate, methacrylic acid, 2-chloroacrylonitrile, 4-chlorophenyl acrylate, 2-cyanoethyl acrylate, glycidyl acrylate, pentabromophenyl acrylate, poly (propylene glycol) methacrylate, poly (propylene glycol) acrylate, 2-propene-1-sulphonic acid and its sodium salt, sulfoethyl methacrylate, 3-sulfopropyl methacrylate, and 3-sulfopropyl acrylate. A particularly desired poly (ethylene glycol) methacrylate is poly (ethylene glycol) ethyl ether methacrylate. The term "poly (ethylene glycol) ethyl ether (meth) acrylate" as used herein includes both poly (ethylene glycol) ethyl ether methacrylate and poly (ethylene glycol) ethyl ether acrylate. Preferred monomers include 2-hydroxyethyl methacrylate (hereinafter HEMA) and polyethylene glycol (meth) acrylates. The term polyethylene glycol (meth) acrylates as used herein includes the polyethylene glycol methacrylates and the polyethylene glycol acrylates and their derivatives and the variable molecular weights thereof. A particularly desirable polyethylene glycol methacrylate is poly (ethylene glycol) ethyl ether methacrylate (hereinafter abbreviated as PEG-MA). This invention has been demonstrated in the following examples by the use of poly (ethylene glycol) ethyl ether methacrylate and 2-hydroxyethyl methacrylate as the polar vinyl monomers. Both poly (ethylene glycol) ethyl ether methacrylate and 2-hydroxyethyl methacrylate were obtained from Aldrich Chemical Company. The 2-hydroxyethyl methacrylate used in the examples was designated Aldrich catalog No. 12 863-5 and the poly (ethylene glycol) ethyl ether methacrylate was designated Aldrich catalog No. 40,954-5. The monomer used in Comparative Examples B-D and Examples 1-10 was a polyethylene glycol methacrylate derivative, poly (ethylene glycol) ethyl ether methacrylate having a number average molecular weight of about 246 grams per mole. Polyethylene glycol (meth) acrylates with an average molecular weight of higher or lower number of 246 grams per mole are also applicable for this invention. The molecular weight of polyethylene glycol (meth) acrylates can vary up to 50,000 grams per mole. However, lower molecular weights are preferred for faster graft reaction rates. The desired range of molecular weight of the monomers is from about 246 to about 5,000 grams per mole and the most desired range is from about 246 to about 2,000 grams per mole. The monomer used in Example 11 was a polyethylene glycol methacrylate having a number average molecular weight of about 360 grams per mole compared to Aldrich Chemical Company, Catalog No. 40,953-7. Again, it is expected that a wide range of monomers as well as a broad range of molecular weights of monomers would be capable of imparting effects similar to polyolefin and poly (ethylene oxide) and would be effective monomers for the purposes of grafting and modification.

The saturated ethylene polymers useful in the practice of this invention are the homopolymers or copolymers of ethylene and polypropylene and are essentially linear in structure. As used herein the term "saturated" refers to polymers which are completely saturated, but also includes polymers containing up to about 5% unsaturation. Ethylene homopolymers include those prepared under either a low pressure, for example, linear or high density low density polyethylene, or high pressure, for example, a branched or low density polyethylene. Low density polyethylenes are generally characterized for a density that is about equal to or greater than 0.9 grams per cubic centimeter (g / cc). Generally, the high density polyethylenes useful as the base resin in the present invention have a density ranging from about 0.94 grams per cubic centimeter to about 0.97 grams per cubic centimeter. Polyethylenes can have a melt index, as measured at 2.16 kilograms and 19 degrees Celsius (° C) ranging from about 0.00 decigrams per minute dg / min) to 100 decigrams per minute. Desirably, polyethylene has a melt index of 0.0 decigrams per minute to about 50 decigrams per minute more desirably from 0.05 decigrams per minute to about 25 decigrams per minute. Alternatively, the polyethylene blends can be used as the base resin in the production of the graft copolymer compositions, and such blends can have a melt index greater than 0.005 decigrams per minute to less than about 100 decigrams per minute.

Low density polyethylenes have a density of less than 0.94 grams per cubic centimeter and are usually in the range of 0.91 grams per cubic centimeter to about 0.95 grams per cubic centimeter. The low density polyethylene polymer has a melt index that ranges from about 0.05 decigrams per minute to about 100 decigrams per minute and desirably from 0.05 decigrams per minute to about 20 decigrams per minute. The ultra low density polyethylene can be used according to the present invention. Generally, ultra-low density polyethylene has a density of less than 0.90 grams per cubic centimeter.

Generally, polypropylene has a semicrystalline structure having a molecular weight of about 40,000 grams per mole or more, a density of about 0.90 grams per cubic centimeter, a melting point of 168 to 171 ° C for isotactic polypropylene and a tensile strength of 5,000 pounds per square inch. Polypropylene can also have other tacticities including syndiotactic and atactic.

The above-mentioned polyolefins can also be manufactured by the use of well-known multiple site Ziegler-Natta catalysts and the most recent single-site metallocene catalysts. Metallocene catalyzed polyolefins have better controlled polymer microstructures than polyolefins manufactured using Ziegler-Natta catalysts, including narrower molecular weight distribution, well-controlled chemical composition distribution, co-monomer sequence length distribution and the stereoregularity. Metallocene catalysts are known to polymerize propylene in atactic, isotactic, syndiotactic and isotactic-atactic stereoblock copolymers.

The ethylene copolymers which may be useful in the present invention may include copolymers of ethylene with one or more additional polymerizable unsaturated monomers. Examples of such copolymers include but are not limited to copolymers of ethylene and alpha olefins (such as propylene, butene, hexene or octene) including linear low density polyethylene, ethylene copolymers and vinyl esters of linear or branched carboxylic acids having 1-24 carbon atoms such as ethylene-vinyl acetate copolymers, and ethylene copolymers and acrylic or methacrylic esters of linear, branched or cyclic alkanols having 1-28 carbon atoms. Examples of these latter copolymers include ethylene-alkyl (meth) acrylate copolymers, such as ethylene-methyl acrylate copolymers.

Free radical initiators useful in the practice of this invention include acyl peroxides such as benzoyl peroxide; dialkyl, diaryl, or aralkyl peroxides such as di-t-butyl peroxide; dicumyl peroxide, cumyl butyl peroxide; 1,1-di-t-butyl peroxy-3,5,5,5-trimethylcyclohexane; 2,5-dimethyl-2,5-di (t-butylperoxy) hexane; 2,5-dimethyl-2,5-bis (t-butylperoxy) hexino-3 and bis (a-t-butyl peroxyisopropylbenzene); peroxyesters such as t-butyl peroxypivalate; t-butyl peroctatoate; t-butyl perbenzoate; 2,5-dimethylhexyl-2,5-di (perbenzoate); t-butyl di (pereftalate); dialkyl peroxymonocarbonates and peroxydicarbonates; hydroperoxides such as t-butyl hydroperoxide, p-methane hydroperoxide, pinane hydroperoxide and cumene hydroperoxide and ketone peroxides such as cyclohexanone peroxide and methyl ethyl ketone peroxide. Azo compounds such as azobisisobutyronitrile can be used.

The poly (ethylene oxide) polymers suitable for the present invention can have a molecular weight ranging from 100,000 to 8,000,000 grams per mole (g / mol). Poly (ethylene oxide) is available from Union Carbide Corporation under the trade name POLYOX®. Typically, poly (ethylene oxide) is a free flowing white powder having a crystalline melting point in the order of about 65 ° C, above which the poly (ethylene oxide) resin becomes thermoplastic and can be formed by molding, extrusion other methods known in the art.

The method for making the polymer blends includes the melt mixing of the desired weight proportions of a mixture of the polyolefin, poly (ethylene oxide), the monomer and a free radical initiator in an extruder and at a reaction temperature. wherein the polyolefin and the poly (ethylene oxide) are converted to a melted state. Thus, polyolefin, poly (ethylene oxide), monomer, and free radical initiator can be added simultaneously to the extruder before the polymer constituents have melted (eg, polyolefin and poly (ethylene oxide)). ethylene).

Preferably, the melt extruder used to mix the melt can introduce various constituents into the mixture at different places along the length of the screw. For example, the free radical initiator, cross-linking agents or other reactive additives can be injected into the mixture before or after one of the polymer constituents is completely melted or mixed. More preferably, the polyolefin and the poly (ethylene oxide) are added at the beginning of the extruder. After melting, the monomer is added to the molten polymers and lower than the extruder barrel, the free radical initiator is fed to the molten mixture. Although not preferred, the scope of the invention will simultaneously include adding monomer and free radical initiator into the molten mixture of polyolefin and poly (ethylene oxide). It is important for the method of the invention that the polyolefin and the polyethylene oxide be mixed with fusion contemporaneously with or before the addition of the monomer and the free radical initiator.While not being limited by any theory, believes that the monomer, in the presence of the free radical initiator, grafts both the polyolefin and the poly (ethylene oxide), thereby allowing articles of the modified polyolefin and modified poly (ethylene oxide) mixture to be made to have a response to higher water As used herein, the term "water response" refers to a loss of tensile or tensile strength to the breaking of a wet film in relation to the dry film tensile strength. or tension to the break.

The amount of free radical initiator added to the extruder should be a sufficient amount to graft from about 1 percent to 100 percent of the monomer onto the polyolefin and the poly (ethylene oxide). This can vary from about 0.01 percent by weight to about 10% by weight of the initiator. Preferably, the initiator amount added to the extruder ranges from about 0.01 percent by weight to about 55 by weight, where all those ranges are based on the amount of monomer added to the molten mixture.

Surprisingly, a film or other thermoplastic article made from the modified polyolefin and modified poly (ethylene oxide) mixture described above responds to water.

The present invention is illustrated in more detail by the specific examples presented below. It is understood that these examples are illustrative embodiments and are not intended to be limited to the invention, but rather are widely considered within the scope and content of the appended claims.

In each of the following examples, a polyolefin / poly (ethylene oxide) mixture was prepared as described. Comparative Example A is a physical mixture of the polymer resins. The blends of Comparative Examples B-D were prepared by a two step process. In the first step, the polyethylene was modified by grafting a monomer thereto. The method of making the modified polyethylene is described in greater detail in the co-pending United States of America patent application having serial number 08 / 733,410 filed on October 18, 1996, the full description of which is incorporated herein. by reference.

In a second step, the modified polyolefin is mixed with poly (ethylene oxide). The properties selected from the materials of Examples A-D are listed in Table 1 below. Examples 1 to 11 data below were made in accordance with the present invention. The properties selected from the materials of Examples 1-10 are listed in Tables 2, 3 and 4.

COMPARATIVE EXAMPLE A A mixture of 60/40 percent resin by weight of a low density polyethylene that has a melt index of 1.9 decigrams per minute (dg / min) and a density of 0.917 grams per cubic centimeter (g / cc) (Dow 5031, available from Do Chemical Company of Midland, Michigan) and poly (ethylene oxide) having a molecular weight of 200.00 grams per mole (POLYOX® WSR N-80 available from Union Carbide Corporation) was fed to an extruder of Haake twin counter screw at a rate of 5 pounds per hour (pound / hour). The extruder had a length of 300 millimeters. Each conical screw had a diameter of 30 millimeters in the supply port and a diameter of 20 millimeters in the matrix. The extruder had 4 heating zones opposite to 170, 180, 180 and 190 ° C. The screw speed of the extruder was 150 revolutions per minute.

COMPARATIVE EXAMPLES B-D For Comparative Examples BD, the low density polyethylene, Dow 5031, was modified by grafting thereto a polyethylene glycol ethyl ether methacrylate (catalog number 40,954-5 available from Aldrich Chemical Company of Milwaukee, Wisconsin and abbreviated hereafter as PEG-MA). The polyethylene glycol ethyl ether methacrylate grafted with polyethylene was prepared using the Haake twin screw extruder described above. The supply to the extruder comprised the simultaneous addition, in the extruder feed throat, of 5 pounds per hour of the low density polyethylene and a specified amount of the polyethylene glycol ethyl ether methacrylate and a free radical initiator, 2,5-dimethyl-2. , 5-di (t-butyl peroxy) hexane, supplied by Atochen, 2000 Market Street, Philadelphia, Pennsylvania, under the trade name LUPERSOL® 101.

For Comparative Example B the polyethylene glycol ethyl ether methacrylate delivery rate was 0.125 pounds per hour and the initiator delivery rate was 0.0125 pounds per hour.

For Comparative Example C, the polyethylene glycol ethyl ether methacrylate delivery rate was around 0.25 pounds per hour and the initiator delivery rate was 0.025 pounds per hour.

For Comparative Example D, the polyethylene glycol ethyl ether methacrylate delivery rate was 0.5 pounds per hour and the initiator delivery rate was 0.025 pounds per hour.

A 60/40 mixture was prepared following the method of Comparative Example A indicated above, except that the modified polyethylene of each example, Comparative Example B-D, was replaced by the unmodified polyethylene. The products resulting from the Comparative Examples had the characteristics indicated in Table 1.

The film processing of the blends was carried out using a Haake extruder as described above with the following modifications. The extruder included a 4 inch slit matrix at a temperature of 195 ° C. The screw speed was 30 revolutions per minute. A cooled coiling roll was used to collect the film. The cooled roller was operated at a sufficient speed to form a film having a thickness of about 4 mils (0.004 of an inch) and which was maintained at a temperature of about 15/20 ° C.

Tests of resistance to stress in dry and wet Dry stress tests were carried out on a Sintech 1 / D voltage tester available from MTS Systems Corporation of Machesny Park, Illinois. The film was cut into a type V dog bone shape according to ASTM D-638. The test was carried out with a grip separation of 20 millimeters and a cross head speed of 4 millimeters per second.

The wet tension tests were carried out on a Vitodyne V1000 mini-tension tester available from Chatillon, of Greensboro, North Carolina. The film samples were placed on the handles and immersed in non-agitated water at room temperature for 30 seconds. The peak voltage, the percentage of tension at break, the energy at break (as an area under tension against the voltage curve) and the module were calculated for each film tested. The percent loss in tension properties from dry to wet was determined for each example.

TABLE 1 Percent Loss in Dry to Wet Properties EXAMPLES 1-4 The 60/40 percent by weight resin blend of a low density polyethylene (Dow 5031) and a poly (ethylene oxide) (POLYOX® WSRN-80) was fed to the Haake twin screw extruder at a rate of 5 pounds per hour. Contemporaneously with the polymer fed to the extruder, the specified amounts of a monomer, polyethylene glycol ethyl ether methacrylate and a free radical initiator (LUPERSOL ® 101) were added to the supply throat. The extruder had 4 heating zones opposite to 170, 180, 180 and 190 ° C. The screw speed of the extruder was 150 revolutions per minute.

For Example 1, the polyethylene glycol ethyl ether methacrylate delivery rate was 0.125 pounds per hour and the initiator delivery rate was 0.0125 pounds per hour.

For Example 2, the polyethylene glycol ethyl ether methacrylate delivery rate was 0.25 pounds per hour and the initiator delivery rate was 0.025 pounds per hour.

For Example 3 the polyethylene glycol ethyl ether methacrylate delivery rate was 0.5 pounds per hour and the initiator delivery rate was 0.025 pounds per hour.

For Example 4, the polyethylene glycol ethyl ether methacrylate delivery rate was 0.75 pounds per hour and the initiator rate of supply was 0.0375 pounds per hour.

The resulting products of Examples 1-4 had the characteristics indicated in Table 2.

TABLE 2 For Examples 1-4 the amount of monomer grafted to polyethylene was 0.65 percent by weight, 1.03 percent by weight, 0.51 percent by weight and 1.13 percent by weight, respectively. The percent by weight of the monomer grafted to the polyethylene was determined by FT-IR and elemental oxygen content as described in the co-pending United States of America patent application No. 08 / 733,410 filed on October 18, 1996, whose Full description is incorporated here by reference. For Example 3, the amount of monomer grafted to poly (ethylene oxide) was determined to be 14.9 percent by weight by proton NMR spectroscopy.

EXAMPLES 5-8 The 60/40 weight percent resin blend of a low density polyethylene (Dow 5031) and polyethylene oxide (POLYOX® WSRN-80) was fed to the Haake twin screw extruder at a rate of 5 pounds per hour. Contemporaneously with the polymer supply to the extruder, the specified amounts of a monomer, 2-hydroxyethyl methacrylate and a free radical initiator (LUPERSOL® 101) were added to the supply throat. The extruder had 4 heating zones set at 170, 180, 180 and 190 ° C. The screw speed of the extruder was 150 revolutions per minute.

For Example 5, the delivery rate of 2-hydroxyethylmethacrylate was 0.125 pounds per hour and the initiator delivery rate was 0.0125 pounds per hour.

For Example 6 the delivery rate of 2-hydroxyethyl methacrylate was 0.25 pounds per hour and the initiator delivery rate was 0.0125 pounds per hour.

For Example 7 the delivery rate of 2-hydroxyethyl methacrylate was 0.5 pounds per hour and the initiator delivery rate was 0.0125 pounds per hour.

For Example 8, the delivery rate of 2-hydroxyethyl methacrylate was 0.75 pounds per hour and the initiator delivery rate was 0.375 pounds per hour.

The resulting products of Examples 5-8 had the characteristics indicated in Table 3.

TABLE 3 EXAMPLE 9 A resin mixture of 30/70 percent by weight of a low density polyethylene (Dow 5031) and a poly (ethylene oxide) (POLYOX® WSRN-80) was supplied to the Haake twin screw extruder at a rate of 5 pounds per hour. Concurrently with the polymer supply to the extruder, specified amounts of a monomer, polyethylene glycol ethyl ether methacrylate and a free radical initiator (LUPERSOL® 101) were added into the supply throat. The extruder had 4 heating zones opposite to 170, 180, 180 and 190 ° C. The screw speed of the extruder was 150 revolutions per minute.

For Example 9, the polyethylene glycol ethyl ether methacrylate delivery rate was 0.25 pounds per hour and the initiator delivery rate was 0.05 pounds per hour.

EXAMPLE 10 A mixture of 80/20 percent resin by weight of a low density polyethylene (Dow 5031) and a poly (ethylene oxide) (POLYOX® WSRN-80) was fed to the Haake twin screw extruder at a rate of 5 pounds per hour. At the same time, with the polymer supplied to the extruder, specified amounts of a monomer, polyethylene glycol ethyl ether methacrylate and free radical initiator were added.

(LUPERSOL® 101) in the supply throat. The extruder had four heating zones set at 170, 180, 180, and 190 ° C. The screw speed of the extruder was 150 revolutions per minute.

For Example 10, the polyethylene glycol ethyl ether methacrylate delivery rate was 0.25 pounds per hour (5 percent by weight addition) and the initiator delivery rate was 0.05 pounds per hour.

The resulting products of Examples 9 and 10 had the characteristics indicated in Table 4. TABLE 4 EXAMPLE 11 A 60/40 weight percent resin blend of a low density polyethylene (Dow 5031) and a poly (ethylene oxide) (POLYOX® WSRN-80) were fed to a twin screw extruder Werner & Pfleiderer ZSK-30 at a rate of 20 pounds per hour. The resin mixture was supplied to the throat of the extruder supply for example, barrel # 1. The extruder had 14 barrels and a total processing length of 1338 millimeters with a screw-to-diameter (L / D) length ratio of 44. The devolatilization zone was located in barrel # 11. The heating system of the extruder consists of seven heating zones. Barrel # 1 is not heated but cooled by water. The barrels # 2, # 3 and # 4 were designated as zone # 1, barrels 5 and 6 as zone # 2, barrels # 7 and # 8 as zone # 3 and barrels # 9 and # 10 as zone # 4 , barrels # 11 and # 12 as zone # 5, barrels # 13 and # 14 as zone # 6 and matrix as zone # 7. The extruder temperatures were measured as the temperatures of these seven heating zones.

The matrix had four openings of 3 millimeters in diameter, which were separated by 7 millimeters. The threads of a polymer were cooled by an air-cooled conveyor belt of 27 feet in length. On the conveyor belt, twenty fans were installed to provide cooling using the ambient air. The cooled yarns were subsequently pelleted by a pelletizer. After the polyethylene and the poly (ethylene oxide) fused in the extruder by the action of cutting heating and conductive heating form the barrels, a polyethylene glycol methacrylate (Aldrich Catalog No. 40,953-7, average number average molecuweight of about 360 grams per mole) was injected through a pressurized injection nozzle in barrel # 5. The injection rate of polyethylene glycol methacrylate was 1.46 pounds per hour. A free radical initiator (LUPERSOL® 101 supplied by Atochem) was injected into barrel # 6 at a rate of 0.048 pounds per hour.

The following barrel temperatures were recorded during the experiment: zone # 1, 182 ° C; zone # 2, 177 ° C; zone # 3, 179 ° C, zone # 4, 180 ° C; Zone # 5, 180 ° C and Zone # 7, 188 ° C. The melt temperature of the extrudate was 204 ° C. The fusion pressure was 193 pounds per square inch. The vacuum of the devolatilization was 25.6 inches of mercury. The pellets produced by the process in this example were converted to films as in Comparative Examples B to D. A film section formed from the composition of this example was placed in water. A silky and soft fabric was obtained. The polyethylene oxide grafted from the film dissolved in the water, making the water thin to the touch.

Although the invention has been described with reference to a preferred embodiment, those skilled in the art will appreciate that various substitutions, emissions, changes and modifications can be made without departing from the spirit thereof. Therefore, it is intended that the foregoing examples be merely exemplary of the present invention and not be considered a limitation thereof.

Claims (20)

R E I V I N D I C A C I O N S

1. A composition of matter comprising a mixture having from about 1 percent by weight to about 85 percent by weight of a modified polyolefin and from about 995 by weight to about 15 percent by weight of a poly (ethylene oxide) modified wherein said modified polyolefin and said modified poly (ethylene oxide) have a total of from about 1 weight percent to about 30 weight percent, based on the total amount of the polyolefin and of the poly (ethylene oxide) of at least one polar vinyl monomer grafted onto said polyolefin and said poly (ethylene oxide).

2. The composition as claimed in clause 1, characterized in that it comprises from about 30 weight percent to about 85 weight percent of said modified polyolefin and from about 70 weight percent to about 15 weight percent. percent by weight of said modified poly (ethylene oxide).

3. The composition as claimed in clause 1, characterized in that it comprises from about 55 percent by weight to about 85 percent by weight of said modified polyolefin and from about 45 percent by weight to about 15 percent by weight of said modified poly (ethylene oxide).

4. The composition as claimed in clause 1, characterized in that said polyolefin is a polyethylene.

5. The composition as claimed in clause 1, characterized in that said polyolefin is a polypropylene.

6. The composition as claimed in clause 1, characterized in that said modified polyolefin and said modified poly (ethylene oxide) have a total of from about 1 weight percent to about 20 weight percent of said grafted monomer the same.

7. The composition as claimed in clause 1, characterized in that said modified polyolefin and said modified poly (ethylene oxide) have a total of from about 1 weight percent to about 10 weight percent of said grafted monomer the same.

8. The composition as claimed in clause 1, characterized in that said polar vinyl monomer is selected from the group consisting of 2-hydroxyethyl methacrylate, poly (ethylene glycol), methacrylates, including poly (ethylene glycol) ethyl ether methacrylate, poly (ethylene glycol) acrylates, poly (ethylene glycol) ethyl ether acrylate, poly (ethylene glycol) methacrylates with terminal hydroxyl groups, acrylic acid, maleic anhydride, itaconic acid, sodium acrylate, 3-hydroxypropyl methacrylate, acrylamide, glycidyl methacrylate, 2- bromoethyl acrylate, carboxyethyl acrylate, methacrylic acid, 2-chloroacrylonitrile, 4-chlorophenyl acrylate, 2-cyanoethyl acrylate, glycidyl acrylate, 4-nitrophenyl acrylate, pentabromophenyl acrylate, poly (propylene glycol) methacrylate, poly (propylene glycol) acrylate, 2 - propene- 1 -sulphonic acid and its sodium salt, sulfoethyl methacrylate, 3-sulfopropyl methacrylate, and 3-sulfopropyl acrylate.

9. The composition as claimed in clause 1 characterized in that said polar vinyl monomer is 2-hydroxyethyl methacrylate.

10. A method for preparing a mixture of a modified polyolefin and a modified poly (ethylene oxide) comprising melt mixing an amount of polyolefin, an amount of poly (ethylene oxide), an amount of a polar vinyl monomer and a sufficient amount of a free radical initiator to modify said polyolefin and said poly (ethylene oxide) by grafting from about 1 percent to 100 percent of said monomer and said polyolefin and said poly (ethylene oxide).

11. The method as claimed in clause 10, characterized in that said modified polyolefin comprises from about 1 weight percent to about 85 weight percent of said mixture and said modified poly (ethylene oxide) comprises from about 99 to about 15 percent by weight of said mixture.

12. The method as claimed in clause 10, characterized in that said modified polyolefin comprises from about 30 weight percent to about 85 weight percent of said mixture and said modified poly (ethylene oxide) comprises from about 70 to about 15 percent by weight of said mixture.

13. The method as claimed in clause 10, characterized in that said modified polyolefin comprises from about 55 weight percent to about 85 weight percent of said mixture and said modified poly (ethylene oxide) comprises from about 45 to about 15 percent by weight of said mixture.

14. The method as claimed in clause 10, wherein said polyolefin selected from the group consisting of ultrahigh molecular weight, high density polyethylene, ultra low density polyethylene, low density polyethylene, linear low density polyethylene and polypropylene .

15. The method as claimed in clause 10, characterized in that said free radical initiator is selected from the group consisting of benzolyl peroxide, di-t-butyl peroxide; dicumyl peroxide, cumyl butyl peroxide; 1,1-di-t-butyl peroxy-3,5,5,5-trimethylcyclohexane; 2,5-dimethyl-2,5-di (t-butylperoxy) hexane; 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3; bis (a- -butyl peroxyisopropylbenzene); t-butyl peroxypivalate; t-butyl peroctatoate; t-butyl perbenzoate; 2,5-dimethylhexyl-2,5-di (perbenzoate); t-butyl di (pereftalate); t-butyl hydroperoxide, p-methane hydroperoxide, pinano hydroperoxide, cumene hydroperoxide, cyclohexanone peroxide and methyl ethyl ketone peroxide.

16. The method as claimed in clause 10, characterized in that said amount of said free radical initiator added to said extruder is from about 0.1 percent by weight to about 10 percent by weight based on the amount of the monomer .

17. The method as claimed in clause 10, characterized in that from about 1 weight percent to about 20 weight percent, based on the amount of said polyolefin and said poly (ethylene oxide) monomer It is added to the extruder.

18. The method as claimed in clause 10, characterized in that from about 1 weight percent to about 10 weight percent, based on the amount of said polyolefin and said poly (ethylene oxide) monomer It is added to the extruder.

19. The method as claimed in clause 10, wherein said polar vinyl monomer is selected from the group consisting of 2-hydroxyethyl methacrylate, poly (ethylene glycol), methacrylates, including poly (ethylene glycol) ethyl methacrylate ether, poly (ethylene glycol) acrylates, poly (ethylene glycol) ethyl ether acrylate, poly (ethylene glycol) methacrylates having terminal hydroxyl groups, acrylic acid, maleic anhydride, itaconic acid, sodium acrylate, 3-hydroxypropyl methacrylate, acrylamide, glycidyl methacrylate, 2- bromoethyl acrylate, carboxyethyl acrylate, methacrylic acid, 2-chloroacrylonitrile, 4-chlorophenyl acrylate, 2-cyanoethyl acrylate, glycidyl acrylate, 4-nitrophenyl acrylate, pentabromophenyl acrylate, poly (propylene glycol) methacrylate, poly (propylene glycol) acrylate, 2- propene-1-sulfonic acid and its sodium salt, sulfoethyl methacrylate, 3-sulfopropyl methacrylate, and 3-sulfopropyl acrylate.

20. The method as claimed in clause 10, characterized in that said monomer is 2-hydroxyethyl methacrylate. SUMMARY A compositional mixture having from about 1 weight percent to about 85 weight percent of a modified polyolefin and from about 99 weight percent to about 15 weight percent of a poly (ethylene oxide) modified. The polyolefin and the modified poly (ethylene oxide) have a total of from about 1 weight percent to about 30 weight percent of a monomer grafted thereto. Included is a method for including the mixture comprising using a single-pass extruder to carry out the steps of blending a polyolefin, a poly (ethylene oxide), a polar vinyl monomer, and a sufficient amount of free radical initiator to graft from about 1 percent to 100 percent of the monomer in the polyolefin and the poly (ethylene oxide).