[1]2 1 7 3 2 9 3 1 7 United States Pateint Office p atented Jan. 24, 1956 2,732,317 MODI-FIED CELLULOSE AND METHOD OF MAKING SAME .5 James Emory Kirby, Wilmington, Del., assignor to E. 1. du Pont de Nemours and Company, Wiliiiington, Del., a corporation of Delaware No Drawing. Application July 8, 1952, 10 Serial No. 297,765 15 CWms. (Cl. 117-63) This inv--ntion relates to a new process for modifyii-ig 15 cellu lose and also to the modified celluloses thereby obtaine d. Cell ulose in its various forrns, e. g., cotton, rayon, cello phane tnd the like, has been a major article of fflm and fiber commerce for a long time, primarily due to 20 the des@irable combination of properties it possesses, e. g., low cost, ready availability, reasonably good physical prop --rties, and a hydrophilicity adequate for many purpose s, e. g., such as to facilitate dyeing and processing in aqueous systems. Many processes have been de- 25 velo ped over the years for modifying cellulose, e. g., to@ basif y it, to strenglhen it, to make it water resistant, and the like. Hoviever, no process for increasing the already relati vely high hydrophilicity of cellulose has hitherto bee n suggested that does not result in a decrease in its 30 othe r properties. Man y of the processes heretofore suggested for the modi fic,ition of cellulose materials having at least one dime nsion relatively attenuated, for instance, treatments to improve antistatic properties, sizing to improve mill- 35 ing and weaving characteristics, filling to improve hand and feel and the like, involve the treatment of cellulose witli vinylideiie polymers, either in solution or dispersion, or altematively by treatment with the requisite monomer follo wed by polymerization. Such processes, while ad- 40 mitte dly modifying the cellulose to change its physic@d prop erties in one or more ways, involve external deposition of the vinylideiie polymer to a major degree and resul t in no increase of hydrophilicity. Usually the revers e is the case ond these modifications appreciably alter 45 the desirable over-all characteristics of the cellulose in one or niore ways, e. g., they have tended to increase stiffn ess. Rec ently many sypthetic films and fibers have been intro duced and have rapidly developed it,-to - commercial r)O nrod i@,et,s of lar,-,. aid extl)andi-q@ markets, primarily bec@ @tise of their extremely good physical properties, partic,al arlv their increased strength and wear resistance as compared with the natural, or modified natural, filmand 4!ber-forming materials. However, these new syn- 55 theti c polymers as a class are deficient in hydrophilicity, i. e., moisture regain. This property is highly important sinc e the v-@riaus processing steps conventionally used in the film aiid fiber industries, such as weaving, sizing, dyei n.-I etc., and even, in some cases, the initial spin- 60 iiing or casting stage, are carried out in aqueous systems. T-lius, despite th(@, present great utility of the syntheti c polymers these would have extended fields of utili' cy were t@,eir hydrophicility to be increased withoiit delet eriously affecting their other desirable physical 65 prop erties. Vari ous attempts have b-.en made to attain this goal perh aps the most import@ant of which, as judged from the cost standi)oint, is that wherein tl-ie synthetic polymer is blendecf with cheaper and more hydrophilic mate- 70 iials of wliich the most available is, of course, cellulose in its various forms. However, despite the - relatively 2 good liydrophilic characteristics of cellulose, it has been found that such high proportions thereof have to be used to produce the desired improvement in hydrophilic characteristics as to detract appreciably from the superior physical characteristics contributed by the synthetic polymers with the result that the end products are not as s,rong as is desired. This invention has an object the preparation of cellulose objects of i-.nproved hydrophilicity. A further object is the preparation of such objects in a shaped form having one dimension extended but at least one dimension lattenuated, i. e., films and fibers. Other objects will appear hereinafter. These obj.-ots are acconiplished by the process of the present invention wherein the cellulosic material in whatever desired form is immersed in a solution of a polymerizable vinylidene monomer containing a quaternary ammonium salt group, the anion of which is of molecular weight less than 150, said solution containing, also in sol,,ition, an initiator for the addition polymerization of said monomer, maintaining the solution at a temperature adequate for polymerization until the polymerization is attained and finally removing all surfpce polymer from the cellulose by careful and thorough extract;on with a solvent for said polynier. BecaLise of convenience, lower cost, @reater safety, and the good solubi!ity c@f most of these quaternary ammonium vinylidene inono-mers and polymers t erein, water is sua used as a solvent for the monomer and as the s ing ageiit to remove surface polymer, the latter conveniently at the boil. The modified cellulose materials thus obtained co@ntaining solely internally depGSited, non-extractable quaternary ammoniu-m vinylidene polymer also constittite a part of this invention. In the process of this invention the starting cellulose material can be preswollen or not. It is convenient not to have to preswell the cellulose, but for quicker and more thorough penetration of the cellulose by the vinylidene rnono-@ner, it is desirable to use preswollen cellulose where possible. The addition polymerization initiators used can be any of those known in the art, provided they al@-P. solu@ole in thf, solvents Lised at the concentrations necessary for in-it;ating polymerization, slach -,ts ,he oxy.op-n yielding initiators, e. g., the persulfates, benzoyl peroxide, with or w@tlicut added reducing agents; the azo coini)ouids, e. g., a,a'-azobis(isobutyramidine hydrochloride) and the like. The temperatures of polymerization can vary froin O' to 100' to 150' C. or higher or lower, dei)ending, ag is ustial in the case of vinylidene polymerizations, on the particular nature of the monomer and initiator system being used. The final step, the critical one in the process, iw,,olies the complete removal from the surface of the treated cellulose of any vinylideiie quaternary ammonium polymer by careful and thoroil-gh extraction with a solvent for the polymer, uslially water at the boil. After such thorough solvent extraction which removes surface polymer, and which may extract from the interior of the cellulose polymer of low enough molecular weight to diffuse out, additional washings do not remove additional polymer, i. e., there is substantially no further weight loss. Phrased another way this means that the intemally deposited quaternary ammonium vinylidene polymer is not extractable. The treated celluloses containing the internally deposited quaternary ammonium vinylidene polymers not only exhibit appreciably improved moisture regain values but also are readily and easily dyed to deep shades with acid dyes, a property long sought for in previous modifications of cellulose. Furthermore, the treated celluloses not only exhibit higher moisture regain figures than controls but lose the absorbed water at a much slower rate on air drying, EL property of high importance m many mfll
[2]2,732,817 3 operations. Fiiially, the treated celluloses possess much improved antistatic properties, exhibiting, in certain instances, as much as an eight hulidred-n-ine hundredfold improvement in this respect. The process of this iiivent;on is of generic - ,tpplicability 5 to those polymerizable, solvent-soluble quaternary e@nimonium salts whose polymerizability is d-,ie to a single ethylenic unsaturation, usually a terminal ethylenic group. The anion of this monomeric salt, as meiitioned previously, is of molecular vveight less than 150 a@-id is gen- 10 erall@Y that of cne of the sh-nple organic or @iiou,@anic mono-, di- or tribasic acids, preferably the mo@-@0- or dibasic acids, pronided only that the quaternary ammoliiulli monomer is solvent-soluble. The single terminal ethylenic unsaturatioii in these vinylidene monoiiiers is bo.- @ded 1;3 through a carboii chain of at least one carbon Nvl-i;ch c,,4n contain etheroxy, carboxyester or carbonamide interzuptions to the quaternary ammonium nitro.-en, one valcnce of vhich is singly ionically linked in mtiltiples of one to three to the anion of a siiiiple acid and any remaining 20 valences of which are satisfied by organic radicals, preferably free of Zerewitinoff active hydrogen. The following examples in which parts are by weight are illustrative of the invention. 9,5 EXAMPLEI A 1.468 part &'-,ein of textile rayon yarn is wet out with water and immersed in 42 pqrts of a 28,6% aqueous solution of 6-methacrylyloxyethyltrimethylanimonium methylsulfate containing 0.1 part a,a'- azcbis(isobutyramidine 30 hydrocliloride). After standing for one hour at room temperature ',o permit complete penetration of the solution into the cellulose, the skein is removed and allowed to drain for one minute. It is the.,i placed in a tightly capped bottle and heated at 70' C. for 16 hours to effect 35 polymerization. At the end of this time, the skein is removed and placed in boiling water for one hour to remove surfz-,ce polymer. The resulting semigelatinous yarn is partly dehydrated with methanol and dried at 70' C. under reduced pressure. There is obtained 2.918 parts 40 of soft, dry yarn, a gain in ,voight of 98.8%. TNvo additional skeins treated in 1'ike manner sliow weigl@it gains of 109 and 115%. The yarn containir@g 98.8% of internally deposited poly-pmethacrylyloxyethyl',rimethylair.monium nietliylstilfate has a denier of 298 compared 4.5 with 151 for the cri.-inal and sliows a moisture regain at 97% htimidity of 75.8% cow-pared to 38.9% for the original. EXAMPLE 11 A s,-ries of textile ra@,op 3,a-,ns 7s trealecl as desribed 50 in Exainple I with varying concen;ration of 6- metliacrylYloxyethyltrimetliylammonium nietliylsulfate. The weight gain due to internally deposited polyn-icr after v,,ashing off surface polymer is given in the following table: 5- 0 llcrecnt P(,re@i,t Yarii i\@'ono mer 11'ei@lit in Troatzontal position and ignited, the flame is extinguished when 111,- 50111, 1 the source of heat is removed; whereas, under like condi1 ---------------------------------------------- co 90.2 60 tions, a sample of the untreated yarn continues to burn 2 ---------------------------------------- I ----- 40 48.5 until cc)mpletely consumed. 3 ---------------------------------------------- 20 18.3 4 ---------------------------------------------- 16.7 16.6 EXAMPLE V 5 ---------------------------------------------- 11.8 10.8 6 ---------------------------------------------- 9.1 8.3 Rayon slaple, 1.219 parts, wrapped iii cheese cloth, is 65 initicrsed in 40 parts of a 30% aqueoils solution of 3- 4 mer and drying as described in Example 1, there is obtained 1.631 parts of dry yarn, representing an 80.5% weigbt gain due to internally deposited poly-dirnethylbeta - riethaerylyloxyethyl - beta - propiobetaine, which exliibits an appreciably higher moisture regain than the control yarn. EXAMPLE IV A. Prepai-ation of pentachloi-obeiizyl bi-oi7iide . To a hot solution of 6.6 parts of pentachlorotoluene iii gfl p,,irts or' carbon tetrachloride is added 4.9 parts (10% excess) ol- N-broi-nosuccinimide freshly crystallized froiii water and 0.1 part of benzoyl peroxide and the reaction mixture heated at the reflux for one hour. The resultant precipitat-. of succinimide is removed by filtratio-n and the carbon tetrachloride is allowed to evaporate from the filtrate at room temperature. Aftcr recrystallizing "I-le resultant solid residue from ethanol, there is obta-tned 4.7 parts (54% of theory) of pentacblorobeiizyl bro-ii-iid,- in the form of white needles melting at 114-5' C. B. Pi-epai-at;07i of p-methacrylylo xyethyldiniethylpeyztacl7loi-obenzylaminoiziun? bi-on?ide To a solution of 25 parts of the above pentachlorobc-.izyl bromide in 72 parts of methyl etllyl ketone is added a solution of 11.5 parts of freshly distilled dimethylaminoethyl methacrylate iTi 11 parts of methyl ethyl ketone. There ;s an imrqe,-iiate separation cl@' the solid quaternar,l amroonilim salt. The reaction mixture is stirred for thirty minutes after addition of the -,imine. The salt is filtered, washed with acetoiie and air-dried. There is ob,ained 32 parts (87% of theory) of non-hygroscopic J3 - riiethacrylyloxyethyldimethylpentachlorobenzylammoniurii bromide as a white, crystalline solid. C. Prepai-atioti of a p-iiiethacrylyloxyethyltrime thylal;zinoniiiin iiielzylsulfatelp-7,nethacrylyloxyethyldimethylpeti tachloi-obeizzylanimonium b7-omide copolynie7- i7itei-iially deposited iii cellulose fibers A 1.513 part skein of textile rayon yam is immersed iii a solution of 3.5 parts of ' 3-methaerylyloxyethylt rimethyl@immorium methylsulfate, 4.5 parts (about a 0.75 molar proportion based on the methylsulfate monomer) of )3 - methaerylylox@,,d;t-pethylpentachlorobenzylammonium broinide and 0.05 part of a,ce'- azobis(isobutyramidine 'iydrochloride) in 3.5 parts ol. water. After standing for 45 minutes at roorn temperature, the yarn skein is removed alid allowed to drain for two minutes. It is then placed in a tightly stoppered bottle and heated at 70' C. for 16 hours to effect copolymerization. The resulting y@irii is stiffened due te @,tirface polyji-icr v.7hich is removed by treating with boiling water for four hours. After partially dehydrating with metlianol, the yarn is dried at 70' C. under reduced pressure. There is obtained 2.44r) p,- lrts of yarn, a gain in weight of 61% due to internallycleposited copolymej-. This yarn exhibits not ojily greater moisture regain values but also greater resistance to burning than does control yari. Thus, when held in a horiAll these yarn simples exhibited improved moisttire re-,ain values coninared to the control yarn. EXAMPLE III A 0.905 part skein of textile rayoii yarn is placed in 15 70 parts of an 80% aqiicous solution of N,N-dimethyl-Nb.-ta - methaerylyloxyetbyl - b,-ta - propiobetaine contaiiiing 0.05 part a,cc'-azobis(isobutyramidine hydrochloride). The yarn and solution are heated at 70' C. for 16 hours @o effect polymerization. On washing off surface poly- ,5 A methaerylyloxyethyltrimethylammonitim chloride contaiiiiig 0.1 part a,a'- azobis(isobutyramidine hydrocliloride.) After allowing one hour for the system to come to equilibrilim, the staple is reiiioved, drained for a few nlinutes and placed i.@i a tightly stoppered bottle which is heated at 70' C. j'or 16 hours. After thorough washing with boiling water to rernove si-irface polymer, the stl)ple is dried at 70' C. under r,-dticed pressure. There is thus oblained 1.703 parts of flexible, soft staple, correspoiiding to a 39.7% weigbt gain diie to internally de-
[3]5 posited poly-beta-methacr ylyloxyethyltrimethylammonium chloride. Treatment of rayon staple iii like manner with the sameconcentration of beta-methacrylvioxyethyltrimethylammonium methylsuffate results in a weight gain of 31.2%. Both treated staples containing interior deposits of the quaternary ammonium polymers exhibit superior moisture regain valiles to those of untreated control samples. EXAMPLE VI i@l,ayon broadcloth, 9.967 parts, is swollen with liquid ammonia, immersed in ice water for about 30 minutes to displace ammonia, and finally immersed and thoroughly rinsed free of any amonia in several changes of distilled water. The thus treated fabric is then placed in a polymerization reactor and covered@with 120 parts of an aqueous 83.3% solution of. beta-methacrylyloxyethyltriinethylammoniummethylsulfate containing 0.1 part aa'-azobis(isobutyramidine hydrochloride). The reactor is heated to 40' C. to effect pblymerization and this temperature is maintained until no further increase in the viscosity of the solution is noted. The fabric is then removed, boiled with water to remove surface polymer, and dried. There is thus obtained 7.278 parts of soft fabric, corresponding to the internal deposition of 37% of poly-betamethacrylyloxyethyltrimethylammonium methylsulfate. The treated broadcloth exhibits superior moisture regain values, antistatic properties, and resistance to flex abrasion. Similar results are obtained under like conditions with various other type cellulose fabrics as given in the table below. In all instances the polymer referted to is internally deposited poly-beta-methacrylyloxyethyltrimethylammoniuria methylsulfate. Percent Moisture Percent Regain Static Flex I,'abric Poly- Propen- .4- brasion mer sity I (cycles) initially Air-dried 40 min. - Rayon Broadeloth-- 37.0 87 14 5.2 344 Do -------------- 0.0 89 4 81 000@ 0 229 Cottou Poplin ------- 29.0 55 24 1. 7 1,169 Do -------------- 0.0 49 2 12,000.0 ---------- Unbleached Cotton i4uslin ------------ 25.0 99 20 13. 5 380 Cotton Tv,,ill -------- 17.7 75 55 3.0 725 A f anti tatic properties reported as resistivityiu measure 0 '9 obinsXIOB; the lower the figure the less the undesirable static effects. EXAMPLE VH A 2.837 part portion of cellophane film is sworen with water, placed in a polymerization reactor, and covere@d with 250 parts of a 30% aqueous solution of betamethacrylyloxyethyltrimethylammonium methylsulfate, containing 0.1 part a,m'-azobis(isobutyramidine Iaydrochloride). After standing for three hours at room temperature the reactor is warmed to about 40' C. to 'mitiate polymerL7ation. When the solution begins to become viscous, the source of heat is removed and the system is allowed to stand at room temperature for 16 hours' The film is washed with methanol, then water and finally dried. There is thus obtained 4.379 parts of clear, flexible fihn corresponding to the internal deposition within the film of 54.5% polybeta-methacrylyloxyethyltrimethylammoniuni methylsulfate. The treated fUm exhibits a superior moisture regain value to that of untreated control. EXAMPLE VIII A 0.913 part skein of rayon yarn is impregnated with a 20% aqueous solution of 1,2- dimethyl-5-vinylpyridinium methylsulfate containing a small amount of a,a'- azobis(isobutyramidine liydrochloride). The impregnated skein is then placed in a polymerization reactor, the reactor closed and the skein heated for 16 hours at 70' C. to effect polymerization. The yarn is then removed and thoroughly water-washed 'to dissolve surface polymer. After drying, there is thus obtained a-0.985 part skein of 2)782,817 6 soft, white yarn corresponding to the internal deposition of 7.9,Yo of poly-1,2-dimethyl5-vinylpyridinium methylsuifate. The treated yam cxhibits a superior moisture regain as compared to untreated control samples. 5 EXAMPLE IX A 1.071 part sample of cerulose sponge is placed in a polymerization reactor and covered with 100 parts of a 30% aqueous solution of betamethacrylyloxyethyltri10 methylammonium methylsulfate containing 0.05 part of ct a,'-azobis(- sobutyramidine hydrochloride) and the react@r closed. lafter being allowed to stand for 1/2 hour at room temperature, the reactor and its contents are heated at 70' C. for 21/2 hours to effect polymerization. The 15 sponge is then removed and thoroughly water-washed to dissolve surface polymer. After drying at 70' C., there is thus obtained 1.227 parts of cellulose sponge corresponding to the internal deposition of 14.6% of polybetamethaerylyloxytrimethylammonium methylsulfate. The 20 treated sponge exhibits superior moisture regain values as compared to Lintreated control samples. EXAMPLE X A 0.888 part skein of rayon yarn is immersed in 15 25 parts of a 33% aqueous solution of beta-methaery lyloxyethyltrimethylammonium methylsulfate containing 0.1 part of potassium persulfate for one hour at room temperature. The skein is then removed from the solution and placed in a polymerization reactor. The reactor is 30 closed and heated for 16 hours at 70' C' to eff-ect polymeriaztion. The yarn is then removed and thoroughly water-washed to dissolve surface polymer. After drying, there is thus obtained 2.105 parts of soft, white yarn corresponding to the internal deposition of 137% of poly35 beta - methacrylyloxyethyltrimethylammonium methylsulfate@ The tre,,ited yarn exhibits greatly superior moisture regain values to those of untreated control yarns. This invention is generic to modified celluloses containing appreciable quantities of solely internally deposited 40 quatemary ammonium vinylidene p6lymers. These new modified celluloses are more hydrophilic in nature than the original cellulose but exhibit unchanged the desirable combination of physical properties of the original cellulosic material. These modified celluloses are obtained by 45 polymerizing the quaternary ammonium vinylidene monomer or monomers involved in and on the cellulose and subsequently removing the externally deposited quaternary ammonium polymer. A convenient method for removing the externally deposited polymer due to the high water50 solubility of most such quaternary ammonium polymers is that of simple water extraction, preferably at the boil because of the shorter times required. The polymerization is effected by simply immersing the desired form of cellulose, regenerated or not, e. g., fabric, yari, staple, 55 paper, film,, sponge, flake and the like, in a solution, usually aqueous, of the particular quaternary ammoiiium vinylidene monomer or monomers desired containing dissolved addition polymerization initiator, heatin.- to the reqtiisile temperature to effect polymerization, and finally, care60 fully removing all surface polymer. Any soluble addition polymerization initiator systeii can be used, usually the water-soluble ones, including the many known free radical generating systems, stich as the peroxy and hydroperoxy compounds, whether or not an 65 added reducing a-.ent activator is present, i. e., the socalled redox systems. The water-soluble azo-type initiators, such as those described in detail in U. S. Patent 2,471,959, are preferred since the redox type initiator systems effect polymerization in general at too low a 70 temperature. The temperature of polymerization can vary from 0-150' C. or higher depending, as is true of all addition polymerizations, on the particular nature of both the initiator system and the quaternary ammonium vinylidene monomer or monomers being used. For obvious 75-considdrations of equipment, degree of control possible,
[4]7 R;id !ppnvenience, it is, preferred to. use those initiator systems whicli pperate with maximlm effectiveness at temperatures rang,.@ig frorn room tertiperati-ire to 100' C. and preferably from 40-80' C. Although the aqueous monomer-initiator systems and aqueous extraction of surface polymer, the latter usually aiid con-veniently at the boil, have been pointed out, and specifically illustrated in the examples, as preferred due ,to the outstariding water solubility of both the monomeric and polymeric otiaternary ammonium vinylidene compounds iiivolved iii the products and processos of ili-is inve-@i'cioii, it is to be understood tilat other solvent based systeii-.s caii be used. For instance, the cellulose materials can be treated with solutions of the requisite quaternary amr,ioiiium vinylideiie monomer or monomers including mincr amounts of other polymerizable vinyl-idene monomers, as poiiited out later, in other inert solvents, such as: @the lower alcohols, for instance, those of less than six carbons,- particularly the lower monoalcohols, inost particularly the lower tertiary monoalcohols, e. g., tert.butaiioi, and the like; the lower ketones, particulariy the lower monoketones of no more than six carbons, e. g., methyl ethyl ketone, and most particularly the lower tertiary monoketoiies, e. g., methyl tert.butyl ketone; the lower nitriles, partic-alarly the lower mononitriles of iio more than six carbons, e. g., acetonitrile; and the like. Similar such solvents can be tised to remove the surface deposited polymer. It is also to be understood that these variot.is solveit systems for both the monomer or monor.- ier/iiiitiator combinations can be anhydrous but are preferably aqueous at levels of from 0-90% water. This invention is generic to modified celluloses contaiiiin.- wholly internally deposited quaternary an-imonium vinvlideile polymers, including copolymers. A preferred class of the quaternary ammonium vinylidene monomers used are those wherein the single terminal vinylidene grotip, CH2=C<, is bonded either directly or mediately throiigh a negative, i. e., electron attractive group, incltiding nuclear carbon of an aromat;c heterocyclic ring, to the quaternary ammonium nitrogen. Generally speakthese quaternary ammonium vinylidene monomers will co-ntain only carbon, hydrogen, oxygen, the quaternary nitrogen and the elements of theqi-laternary amiiionium anion. In the particularly pr.-ferred, because of read,'er availability, class of these quaternary monomers the sin,-le I?oiymerizable terminal vinylidene group is ioin-,-d to a quaternary E-,mmonium nitrogen through a @arbop, oxy-ir@terrliped carbon, or carboxy-interrupted carbor, chaiii, witti one valence of the said quaternary ammor,ilim nitro.-en being satisfied by a single ionic linkage to the qnion of a simple, i. e., not complex, or.-anic or inorg-,inic acid, preferably stron.- and of molecular weight less tli,- in 150 atid the rcmaining valences of the said qti,itern,,iry nitrogeii being satisfied by monovalent orrpdic-,ils preferably solely hydrocarbon free of alipiiatic unsaturation and of no more than eight carbons c-,Acli. it will be noted from this description of quatemary ammonium vinylidene monomers that in polymer form, as intemally deposited in the modified celluloses of this inveiition, the quaternary ammonium groups will be present as extralinear components on and not in the said polymer chain. The preferred quaternary ammonium vinylidene monomers are those wherein the single quaternary aDIMOnium nitrogen is (a) that of an N-substituted pyridinium iiucleus, hydrocarbon except for the pyridinium nitrogen and (b) a trihydrocarboar@imonium nitrogen which is bonded to the alkylene, -R- radical of a group, -(CO),tOR-, wherein ii is a cardinal number not greater th,,tn one, -",hich in turii is bonded either directly or through another alkylene -R- radical to the terminal vinylidene group. The quaternary ammonium vinylidene moliomers used in preparing the modified celluloses of this inveiition thus each have a single quater8 nary ammonium nitrogen, one valence of which is bonded to the single terrninal vinyliden,- grotip tirough a multiply bonded carbon, includiiig the carbons of an aromatic rin.@ such as the pyridi-@iiiim ring, or thr-,ugh, either directly or mediately, an ether oxygen or an ester linkage, either as a carbonyl-oxy or oxy-carbonyl linkage. The said_single quaternary ammo-@i-lum nitrogen will have a further valence ionically bonded singly in multiples of one to three and usually onc to two to an anion of 10 a simple organic or inorganic acid, preferably a slrong acid. Tl-.e term simple acid is used as in the Rules for Inor anic Nomenclature in coitrast to the polyacids. .9 See' for instance, J. Am. Chem. Soc. 63, 889, eL seq (1941). The remaining valences of the said single 15 quaternary animonium.nitrogen are satisfied by organic radicals, preferably hydrocarbon radicals of one to eight carbons free of aliphaticunsaturation, two of which may be together joined to form with the said quaternary ammonium nitrogen a ring. GeneraHy, these said remain90 ing valences will be satisfied by solely hydrocarbon radicals having a total of three to twelve carbons, and most preferably by saturated aliphatic hydrocarbon radicals of a total of from two to six carbons with the lower (one to two carbon) saturated aliphatic hydrocarbon radicals 25 being particularly preferred. Particularly useful are those quaternary ammonium vinylidene monomers wherein the single quaternary ammonium nitrogen is singly ionically bonded as described above to the anion of a simple acid and singly to the 30 sole vinylidene group throu h (a) an oxy-alkylene radical .9 or (b) a carboxy-alkylene radical or (c) pyridinium ring carbon, any remaining valences of the nitrogen being satisfied by solely hydrocarbon radicals free of aliphatic unsaturation. 'fhus, in one class of the quaternary am35 monium vinylidene monomers, the quaternary ammonium nitrogen is joined to the Cnffi. radical of a -(CO),n@OCnH2ngroup wherein m is a cardinal number not greater than 40 one and n is an integer from 1 to 6, with the remaiiiing free valence of the said group bein-. bonded directly or mediately through a divalent saturated aliphatic hydrocarbon radical to the single vinylidene group. In the other class, the quatemary ammonium initrogen is that of a pyridiriium nucleus, hydrocarbon except for the 45 nitrogen, which is bonded from carbon of the pyridinium nucleus directly to the single vinylidene group. In both classes the remaining valences of the quaternary ammonium nitrogens are satisfied by monovalent hydrocarbon radicals free of aliphatic unsaturation and generally to50 taling no more than twelve carbons. These types of quaternary ammo-nium vinylidene monomers and polymers are generally well known in the art. See, for instance, U. S. Patents 2,138,763; 2,484,420; 2,484,430; 55 2,487,829; 21540,985; 2,572,560; 2,572,561 and the copending applications of Bamey Ser. No. 216,838, filed March 21, 1951, and Ser. No. 267,495, filed Jantiary 21, 1952, now Patent No. 2,677,699. Particular examples of these various quaternary ammonium vinylidene monomers include those of the vinyl 60 pyridinum type such as: 1-methyl-2-ethyl-5-vinylpyridinium methylsulfate, I-ethyl-2-vinylpyridinium chloride, 1methyl - 5 - ethyl-2- vinylpyridinium-p-toluenesulfonate, 1benzyl-5-ethyl -4-vinylpyridinium bromide; those wherein the quatemary ammonium nitrogen is bonded to the 65 vinylidene group through an alkylene ether linkage such as: beta-vinyloxyethyltrimethylammonium chloride, betavinyloxyethyidiethylbenzylammonium bromide, gamrnavinyloxypropyltrimethylammonium methylsulfate; those herein the quaternary ammonium nitrogen is bonded to w 70 the single vinylidene group through an alkylene carboxy ester or alkylene carboxy ester alkylene linkage including both the oxy-carbonyl and carbonyloxy types of carboxy ester linkqges such as: betaacrylyloxyethyltrimethylammonium chloride, gammamethacrylyloxyprop7,5 ylb'enzylethylmethylammonium methylsulfate, 4-(alpha-
[5]2,732,817 9 ethylacrylyloxy)cyclohexylmethylbutylammonium P-toluenesulfonate and the like. In the case of homopolymers of the quaternary ammonium vinylidene monomers where' the vinylidene group is bonded to the quaternary in nitrogen through an ether linkage polymerization initators of the ionic type are preferied. Minor amounts of other addition polymerizable monomers,- preferably those contaiiiing a single vinylidene croup, can be used in prethe new products of @this invention, such as the ,oi parmg vinylidene carboxylic acids and their, ester, amide, nitrile, and other derivatives e. g., acrylic acid methacrylamide, acrylonitrile, and the like; unsaturated esters of carboxylic acids, e. g., vinyl acetate; polymerizable ethylenically unsaturated hydrocarbons, e. .-., styrene and the like. However, it is necessary that the internally deposited polym-.r essentiauy consist of the above defined quaternary ammonium vinylidene monomers in combined form. The amounts of solely internary deposited polymer can vary from as low as 1% to as high as 200% or higher by weight of the starting cellulose. However, as fflustrated by the examples, the intemally deposited quaternary ammonium polymer should be at least about 5% by weight of the cellulose for the modified products to exhibit appreciably different properties. Because of the greater improvement in hydrophilic properties exhibited, those modified celluloses are prefeffed wherein at least 25% by weigbt of the cellulose of quaternary animonium vinylidene polymer is internauy deposited. The internal deposition in cellulose, according to the process of this invention, of appreciable quantities of polymers of quaternary ammonium vinylidene monomers renders the thus treated cellulose extremely more hydrophilic in nature but, surprisingly, does not change any of the desirable characteristics of the ceflulose, particularly the softness of the hand and feel. This latter is particu_ larly surprising in the light of the previous art on the restilts of treating cellulose with vinylidene monomers and polymers. The thus treated cellulose. is exceffent for blending purposes with the synthetic fflm- and fiberforming polymers, conferring improved hydrophilic properties to the blends at relatively low concentrations. @@tf Special effects can be achieved in the treated ceuuloses by using partictilar types of quaternary ammonium monomers, for instance, flameproofing through use of quaternary monomers containing high proportions of halogen or by interchanging the simple acid anion of an internally deposited quaternary polymer with a polytungstic@ acid, or fungicidal properties, particularly important in cellulose in sponge form, through use of quaternary ammonium monomers carrying benzyl substituents. The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations are to be understood therefrom. The invention is not limited to the exact details shown and described for obvious modifications will occur to those skilled in the art. What is
