CA1320128C

CA1320128C - Biostatic and biocidal compositions

Info

Publication number: CA1320128C
Application number: CA000555145A
Authority: CA
Inventors: Graham John Hamilton Melrose; Concetta Maria Kleppe; Jeffrey Wayne Langley; Jeffrey Mark Stewart; Jacobus Van Dyk
Original assignee: Graham John Hamilton Melrose; Concetta Maria Kleppe; Jeffrey Wayne Langley; Jeffrey Mark Stewart; Jacobus Van Dyk; Biopolymers Limited; Chemeq Investments Pty Ltd; Graham Melrose And Associates Pty Ltd; Chemeq Pty Ltd
Current assignee: CHEMEQ Pty Ltd
Priority date: 1986-12-23
Filing date: 1987-12-22
Publication date: 1993-07-13
Anticipated expiration: 2010-07-13
Also published as: ATE101860T1; HK103394A; NO883639D0; WO1988004671A1; NO173737C; NZ222979A; NO883639L; DK469788A; IN166555B; MY102278A; JP2857756B2; EP0339044B1; DK174224B1; US5290894A; EP0339044A4; ZA879640B; AU616166B2; KR890700617A; EP0339044A1; AU1086488A

Abstract

ABSTRACT

A process for rendering matter biocidal or biostatic using polymeric compounds having a polyacrolein sub unit in aldehyde, hydrated, hemi acetal or acetal form. The polymeric compound may be used to treat or be included in, a wide range of products.

Description

- 1~20~2~

BIOSTATIC AND BOICIDAL COMPOSITIONS
The present invention relates to a process for rendering matter biocidal or biosta~ic.
As is well known a biocidal substance kills micro-organisms and a biostatic substance inhibits the growth of microorganisms; microorganisms including for example, bacteria, fungi and viruses. It is also known that aldehydes such as glutaraldehyd~ and formaldehyde are biocidal or biostatic and that substrates or substrate materials may be treated with such substances or ; 10 compositions to render them at least temporarily biocidal or biostatic. The disadvantages of the use of such substances or such compositions is that the aldehydes have penetrating, obnoxious odours and are volatile thus rendering them unsuitable for long term biocidal or biostatic treatment of substrates or substrate materials.
As a result of microbial action, untreated substrates or substrate materials may be subject to deterioration or production of odours or formation of obnoxious or slippery slime or mildew or give rise to inflammation or transfer of disease. Thus, it is desirable that such substrates or substrat~ materials can be treated to render them biocidal or biostatic.
Another disadvantage of,such conventional biostatic or biocidal compounds or compositions is that they are relatively low molecular weight and therefore pass relatively freely through biological membranes such as the skin or the intestinal wall and in both cases, into the blood stream of humans or animals where they may give rise to antigenic, allergenic or toxic effects; similar destructive or toxic results may arise from for example, passage through the roots or outer membranes of fruits or vegetables. Thus, there is a need for biostatic or biocidal ~_.

~ A ~

.
.

c~pounds or compositi~ns wh~ch do n~t readily pass through biological membrane6.
It has now been di~covered that polymeric compound~
having, illustratively, the repeating unit - CH2 - ~H -,CH2 ~
CHO CHO
may be utilized as biocidal or bi~stat~c compound~ and f~r th~ treatment of ~ub~trate~ or ~ub~trate ~aterial~ to render them biocidal or biostat~c~ ~owever, it is stressed th~t ~uch polymeric comp~u~ds haYing thi~ repea~ing unit do no~
exist at equili~rium, entirely in these illustrated open chain forms ~n which the aldehyde groups are entirely un-associated. Specifically, we have discovered that polymer~ or ~opolymers o acrolein or of an aldehyde-derivative of acrolein may be utilised a~ biostatic or biocidal compounds and for the tre~tment of substr~te~ or ~ubstrate materl~ls to render the~ bl~tat~c or b~ocldal.
Specifically, the preqent invention pxovides ~
. process for rendering mat~er biocidal or biostatic, which process comprises applying to or incorporating in the matter a biocidally or biostatically effective amount of a polymer compound having the polymeric unit ~5 or thi3 unit i~ hydrated, he~i-acet~l or aoet~l form o~ the ~orDlul~0 \ CH / ~ \ CH2 /C t~
RO/ \ OR U~/ O ~ OH
(a) (b) :
'~ ~

,; ~ .

3a -1~20128 _ /CH2 ~ / H2 ~ CH / \ /CH2 l~û /¢ \ O ~ , CH \ ,, CH \ / CH \

\ /
_ x fH
(c) /CH\
10 ~ ~ / CH2 O\ /
~H .gd3 CH= CH2 ~e) CH 3CH2 C~ 2 0~ CH2 /0\ ~C~12 / H\ /

2 0 / CH \ Cl~ CH2 ~J0~ \ OH

t1') wherein R i~ hydrogen and x i~ an integer of 1 or more; or a composition containing s~id polymeric compound incorporated in or bound to a ~ul~strate or sub~trate material .
~he invention lies in the recognition of the similaritie~ in structure betwee3l ~lutaraldehyde, ~ which is a knowYl bacteriostat and bacterioeide, and polymer~ or : copolymer~ of. acrolein or of an aldehyde-derivative o~
:acrolein. In the case of poly~crolein, for example, at equililbri~lm the structur~ take on a number of difiEerent forms; it is gene~rally agreed (~. Bergm~n, W.T. Tsatsos and P~.F. FischerO J. Polymer Sci: Par~ A,:1965, 3485; P~.C.
Schulz:, Vinyl ~olym. ,~ 1967, 1, 403; L. Hunter and J.W.
E~orbe~,: J. Polynler Sci: Part ~, 1965, 3~ 3471 that sub-un~ ~s of polyacrolein produc~d ~y a free radical inducing agent have the s~r~actures below ~ (a1, R~

~`: : . :

_ 3b - ~ 3~0~8 ~ ~C~ ~ ~CH2 ~ ~CB~

RO/ \OR HO/ i o / \OH

(a, (b) .

~i~
) :
.

132~128 \ CH f ~ ~ CH / ~ CH / 2\ \CH /

HO \ ~ \ O ~ \OH HO/
_ ~ X ' ~) x = integers ~f 1 or mor e HO
(c) \ CH
CH

(d) Figure 1 in which either the form (d) or the tetrahydropyran rin~-form (b) or the fused tetrahydropyran ring-form (c) predominate. l3C-~MR analysis of polyacrolein produced by a free radical inducing agent (free radical catalyst)showed negligible aldehyde carbon, which is consistent with the above structures; the spectrum also showed a number of aliphatic CH's and CH2's and a number of O-C~-O's which are all expected from the above variety of structures.
In keeping with proposals of R.C. Schulz, vinyl Polym., 1~67, 1, 403, the 13 C-NMR spectrum of polyacrolein produced by an ionic catalyst is consistent with the above structures for:the polymer and additionally, the presence of structures~(a) and (b) of Figure 2.

O
\CI H /
H=CH2 ( ~ ) :. :
H = CH2 :,CH :CH2 CH \ / CH2 \ / \ / CH2 \ ~ ~ \
O ~H ~ H ~ O

Ho \ OH ~ ~ Ho / \ OH
:~ :

: Figure 2:: :
:` : :

: . : :
. .. . .

.

~ 5 ~ ~32~128 The C-NMR spectrum of a copolymer of acrolein diethylacetal : acrylic acid was consistant with the polymer hav.ing repeating units illustrated by Figure 1 (a); R =
CH3CH2.
Glutaraldehyde is proposed to exist in the following forms (A.D. Russell and D. Hopwood, "Progress in Medicinal Chemistry", Vol. 13, Eds. G.P. Ellis and G.~.
West, North Holland Publishing Company, 1976):

CIH / CH \ ICH2 / CH2 \ cH2 CHO CHO CHO / H \
HO OH
(a) (b) /CH2\ / CH2\
~H2 l H2 ICH2 CH2 HO / OH HO OH / CH \ / ~ OH
(c) (d) / CH2\
H ~ \ O / \ O

(e) ' ~o/\o/ ~o/ ~ '~1 : (f) x,y,~ = integers of l or more : ~ Figure 3 :

" - 6 - ~ 2~ 1~g The ' 3C-NMR analysis of glutaraldehyde showed that very little of the glutaraldehyde ~less than 5~) existed in the free aldehyde form (a). There were many aliphatic CH2 resonances evident in the spectrum with the major peaks numbering eleven. There wer~ also many O-CH-O resonances with nine major peaks. This supports the existence of the above cyclic structures as the linear forms of glutar-aldehyde would not give rise to so many different resonances.
~ An added advantage of these pol~mers or copolymers of acrolein or of an aldehyde-derivative of acrolein is that their hydrophilicity/hydro-phobicity or water solubility/oil or iipid solubility may be widely adjusted by the inclusion or exclusion, respectively, of hydrophilic comonomers, or example, acrylic acid, vinyl pyrrolidone, vinyl or acrylic monomers containing oxygen~
containing groups for example, hydroxyl groups, or ether groups or carboxyl groups, or other similar hydrophilic monomers which will now be apparent to those skilled in the art. Normally, the homopolymers of acrolein are water-insoluble and are thus suited to applications where their elution by aqueous media are not desirable as in sprays for agricultural or veterinary purposes or in applications where the utility of the polyacrolein is sought in oil phases such as some cosmetic/toiletry preparations or foods or engine oils; alternatively, the inclusion of a high percentage of hydrophilic comonomer for example, acrylic acid renders the resulting copolymer suited to use in 3C hydrophilic media which is more usual in cosmetics, toiletries, pharmaceuticals or food substances. Water-dispersable or water-soluble copolymers of acrolein, for example, the 90:10 acrylic acid: acrolein copolymer is especially suited as a sterilent, sanitiser, antimicrobial or preservative in cosmetics, toiletries, pharmaceuticals or food substances. A particular application which we record is that we project copolymers of acrolein or of a carbonyl-deri~ative Gf acrolein may be dissolved in an aqueous ~

....

' : . , `` _ 7 _ 132~2~
solution or in a gel-like medium formed through, for example, the presence of carboxymethylcellulose and then the resulting solution or gel used as a rectal suppository to combat the transmission of AIDS virus amongst homosexuals.
5 Also the solution or gel could be enclosed in a s~all tube (as toothpaste is conventionally dispensed) - the cap of the tube incorporating a syringe-needle which is made available to drug addicts who are in danger of transmitting ~IDS
through unclean injection-techniques; o~ course, the 10 storing of the syringe-needle in the solution or gel would have a biostatic or biocidal effect against the aids micro-organism.
A further advantage of the said polymers or copolymers of acrolein or of a derivative of acrolein is 15 that their biostatic or biocidal activities appear to be less pH-dependent than giutaraldehyde (see S.D. Rubbs et al., J. Appl. Bact., 1967, 30(1), 78).
An advantage of using an aldehyde-derivative of acrolein is absence or greatly reduced acrid smell, compared 20 with acrolein, during the ~olymerization. Of course, however, all ~inal polymers and even those prepared from acrolein are essentially odour-free.
Substrates which can be treated with the compounds of the invention include cellulose, modified cellulose, 25 regenerated cellulose, rayon, polymers of plastic materials such as vinyl polymers, acrylic polymers and polyesters, rubbers and various materials such as ceramics, glass, silica, concrete, masonry, miner~ls and earths.
Examples of substrate materials which may be made 30 by such substrates are:
Airconditioner filters, air-line wipes, aprons, bags for laundry, bandages or adhesive bandages, bathroom tiles or grout, bricks, car or other carpets, catheters and related hospital instruments made from plastic or glass, clothing 35 including underwear, cloth wraps for food, concrete, cotton-balls or cotton tips (buds), diapers, disposable towels, drapes (domestic, commercial, industrial or hospital), ` - 8 - ~32 ~1~8 disposable cardboard or plastic food boxes, face masks (hospital or industrial) bed covers, inners of shoes, ironing board covers, jumpers or cardigans, nursing pads, paint for ships' hulls or underwater pylons, paper plates 5 and cups, water reservoirs or swimming pools or water-treatment chemicals, rubbish bins made from cardboard or plastic, sanitary napkins or feminine hygiene tampons, sheeting for babies' or incontinent persons' beds, shelving paper, shower curtains, socks, sterile gloves, sterile 10 overalls, teatowels, telephones - diaphragms for mouth pieces, tents, tissues, handkerchiefs, toilet paper, toothbrush nylons, towels, wall paper, window awnings or other like structures made from canvas plastic etc., wipes, mops, sponges, wood or wood-impregnants.
It has now also been discovered that polymerization of acrolein or an aldehyde-derivative of acrolein, with or without other comonomer in the presence of a substrate or substrate material causes the polymer to chemically bond to the substrate such as through graft polymerization. This 20 has the advantage that the biocidal or biostatic agent is not readil~ removed from the substrate. Thus, the effect of the biocidal or biostatic agent may be longer-lasting than in cases where there is no chemical bond.
The rendering of the substrate biocidal or 25 biostatic either prevents microbiological degradation of the substrate, prevents the production of odours which may result from degradation of the substrate or from the degrad-ation of chemical compounds contained in or within the substrate. This rendering also prevents the substrate from 30 being a vector of inflammation or disease. Further, mould, lichen or other similar formation on the substrate may be prevented. The biostatic or biocidal agent of the present invention may be associated with materials from which substrates are made, so as to be incorporated into the final 35 product or alternatively, the finally fabricated substrate may be suitably treated to associate it with the biocidal or biostatic agent.

-9- 13201~
~. . .

A polymeric biocidal or biostatic compound may therefore be provided having the polymeric repea~ing unit - CH~ - CH2 - ~H -HO HO
or this repeating uni~ in hydrated, hemi-acetal or acetal forms described earlier (Figures 1 and 2), such biostatic or biocidal compound having the repeating unit(s) bPing derived from a pol~mer or copolymer of acrolein or of an aldehyde-derivative of acrolein.
A composition of matter may also be provided, comprisîng a polymeric biocidal or biostatic compound having the polymeric repeating unit - CH2 - ÇH - CH2 - CH -~0 I!~HO

or this repeating unit in hydrated, hemi-acetal or acetal forms described earlier (Figures 1 and 2), such biostatic or biocidal compound having the repeating unit(s) being derived from a polymer or copolymer of acrolein or of an aldehyde-derivative of acrolein bound to a substrate or substrate material.
The invention provides a proces~ for preparing a polymeric biocidal or bio tatic compound having the polymeric repeating unit C~ ~ CH2 - ~H
HO ~O
or this repeating unit in hydrated, h~mi-acetal or acetal form~ described earlier (Figures 1 and 2), such biostatic or biocidal compound havinq the repeating unit(s) being derived from a polymer or copolymer of a~rolein or of an aldehyde-derivative of acrolein such polymerisation taking place in the presence of a polymerisation~ inducing agent;
the agent is either a free-radical initiator,.or an ionic initiator.
A method of producing a composition of matter may therefore be provided which comprises polymerizing acrolein or a deriv~tive thereof in the presence of or with a . ~, ;

. ~ .. . ... . . . .
.

-` 13~0128 substrate or substrate material preferably in the presence of a polymerization inducing agent. The polymerization inducing agent is preferably selected from gamma radiation, such as is produced by a radioactive cobalt source.
The invention will now be illustrated by the following non- limitative examples.

Example 1 Preparations and Structures of Pol~crolein (a) Using a free radical inducing agent (free radical catalyst): 9.64g distilled acrolein and 25g methanol were placed in a lOOml round bottom flask and purged with nitrogen. 0.525g benzoyl peroxide was added and the solution stirred under nitrogen at 60 degrees centigrade.
15 The reaction was allowed to continue for a total of ca. 88 hours. After this time the reaction solution had become strongly yellow in colour and had a solids content of 30.5%.
13 C-NMR (300MHZ) ~(relative to d4-methanol at 49.00): 33.27 (CH); 33.53 (CH); 33.79 (CH); 33.87 (CH2);
20 37.03 (CH); 37.29 (CH); 37.54 (CH); 37.64 (CH2); 97.15 (CH); 103.37 (CH); 104.34 (CH); 139.36 (CH);
139.78(CH2); 196.72 (CH). The 13C-NMR spectrum shows some residual acrolein with the aldehyde carbon at ~196~.72 and the vinylic CH2 and CH at ~139.78 and ~139.36, respectively;
25 apart from the ~196.72 (CH) resonance absorption, there was no other attributed to -CHO. The spectrum is consistent with polymeric acrolein consisting of fused tetrahydropyran rings and some free dihydroxy me~hyl groups. The rings exist in either the boat or chair configurations giving rise 30 to more chemical shifts than may be expected.
A similar polymerization of acrolein was also carried out: 25.02g methanol was placed in a reaction vessel fitted with ~a thermometer, reflux condenser and nitrogen inlet tube. 0.528g of benzoyl peroxide was added 35 and 9.65g of distilled acrolein was added. The system was purged with nitrogen and heated in an oil bath at 60 degrees centigrade with stirring, for 24 hours; when a solids - 11 1 32 ~ 1 28 determination indicated 20% conversion; total conversion was 40~ after a further 48 hours heating.
Typically, as an indication of molecular weight, the polyacrolein was found to have a retention time which was shorter than that of polyethyleneglycol 10,000 on a Porasil GPC 60~Angstrom column using a Waters Associated Model ALC/GPC 204 liquid chromatograph fitted with a differential refractometer R401.
tb) Using an ionic catalyst: 1.6g distilled acrolein was made up to 20ml with deionised water in a 200ml beaker and then, ca. 0.5ml of 0.2M sodium hydroxide added with stirring to pH ca. 10-11. The solution became cloudy and a white precipitate began to formO The contents were stirred for a further ~ hours and then filtered. The precipitate was washed thoroughly with deionised water until the filtrate was neutral. The product was dried under vacuum and was a white-pale yellow, fine powder; it readily dissolved in methanol - and conveniently and importantly, could be evaporated down to dryness and then again, dissolved in methanol or other solvents. In a similar determination to the above, the polyacrolein was found to have a retention time which was shorter than that of polyethylene glycol 10,000. ~ C~NMR (300MHz) ~trelative to d9-methanol at 49.00): 19-31 (CH2); 35.95 (C~2); 37-42 (CH);
25 62-73 (CH2) 73-al ~CH); 92-95 (CH); 96-103 (CH); 114-120 (CH2); 134-141 (CH); 196.0 (CH).

Example 2 _reparation of 90 1O Acrylic Acid: Acrolein Copolymer 6.489g distilled acrylic acid, 0.56g distilled acrolein and 15g methanol were placed in a 50ml round bottom flask and purged with nîtrogen. 0.33g benzoyl peroxide was added and the solution stirred under nitrogen at 60-65 degrees centigrade. The reaction was continued for ca. 66 hours. After this time the contents of the flask had become very viscous, having a solids content of 57.7% (indicating 100~ conversion).

-;~C(~ S trC~ rk .... . ~

- 12 - ~320128 A sample of the viscous mate~ial was placed on a petri dish and dried on a hot plate to remove solvent.
Drying was completed in an oven at 80 degrees centigrade and a transparent, slightly yellow coloured polymer was 5 obtained. The copolymer is completely soluble in warm water (ca. 50 degrees centigrade) and once dissolved remains so, even on cooling the solution.
In order to ensure that the solids obtained were polymeric, a simple dialysis experiment was perfor~ed: 109 10 of an aqueous solution containing 0.65% solids was placed in a dialysis tube. This was irrigated with water continuously for ca. 66 hours. The solution in the dialysis tube was then recovered and the solids content determined at 0.68~.
Since the solids were completely retained and the lower 15 limit for solids penetration through the dialysis tube is 2000 mwt, we conclude that the solids are polymeric 2.8g of acrolein diethyl acetal was placed in a 100 20 ml round bottom flask and the contents purged with nitrogen.
A solution o~ 0.216g potassium persulphate in 7.5g water was added with stirring, under nitrogen. The 1ask was placed in an oil bath at 60-70 degrees centigrade and stirred for ca. 20 hours. A yellow solid was recovered and dried at 50 25 degrees centigrade; weight 0.915g.

Exam~le 4 4g distilled acrylic acid, 4.81g acrolein diethyl acetal and 15g methanol were placed in a 50ml round bottom 30 flask and purged with nitrogen. Then 0.3g benzoyl peroxide was added and stirring continued under nitrogen at 60-65 degrees centigrade for 70 hours ~solids determination indicated a 50~ conversion). 13C-NMR (300MHz) ~(relative to d4-methanol at 49.00): 15.58 (CH3); 18.31 (CH3 ); 35.52 35 (CH2); 36-24 (CH2);~ 37.07 (CH2); 42.36 (CH); 42.85 (CH);
~8.32 (~H2)~ 130.00 (CHI; 131.57 (CH2); 178.51 (CH).

Example 5 - 13 - 1320128 3.8g of acrolein diethyl acetal, 3.3g vinyl pyrrolidone and lOg methanol were placed in 50ml round bottom flask and thoroughly purged with nitrogen. 0.71g azobisisobutyronitrile was added and the flask heated in an oil bath at 60-65 degrees centigrade, with stirring under nitrogen for 72 hours when the conversion was 44%. The copolymer was found to be soluble in methanol.
Example 6 In a similar technique to the above, 3.9g acrolein diethyl acetal, 1.16g acrylic acid, 7.5ml water and 0.216g potassium persulphate were heated under nitrogen, with stirring in an oil bath at 60-70 degrees centigrade for ca.
24 hours when a white waxy material was recovered; it was insoluble in water, but swelled in methanol, acetone, tetra-hydrofaran or methyl ethyl ketone.

Example 7 A similar result was achieved through heating and stirring in the usual way to the above: 14.5g methanol, 3.62g distilled acrolein, 1.21g distilled acrylic acid and 0.265g benzoyl peroxide. After 40 hours the conversion was 40~.

Examples 8-11 A 50:50 mixture of monomers was treated as follows:
2.35g distilled acrolein, 2.88g distilled acrylic acid and 14.5g methanol were placed in a ~Oml round bottom flask and flushed with nitrogen. 0.2625g benzoyl peroxide was added and after heating at 60-70 degrees centigrade for 48 hours the conversion was 70%. The polymer swelled in methanol but was insoluble in water.
Similar preparations were achieved with different ratios of the monomers acrolein: acrylic acid namely, 30:70 (Example 9), 10:90 (Example 10), 2.5:97.5 lExample 11~. The products from Examples 10 and 11 were soluble in water and retalneJ by dialysie tubing of exclusion 2,000mwt.

..... , . ~ - , , .

~ 3~128 Ex ample 12 In a similar preparation to the above, 42%
conversion was achieved of a polymer which swelled in methanol or water, from 1.8g acrolein, 3.3g vinyl pyrrolidone and 0.071g azobisisobutyronitrile.

le 13 30mg benzoyl peroxide was added to a solution of 1~ 1.02g polyethyleneglycol acrylate and O.Sml acrolein in 5ml methanol. The mixture was stirred and heated to reflux for .~ 48 hours and gave 90% conversion; the residual oil (1.2g) was chromatographed on Sephadex LH-20~(189) in me~hanol.
` The structure of the resulting polymer was confirmed by NMR
analysis.
Examples 14-19 Whatman 5.5cm filter paper was immersed in the following solutions and irradiated by a cobalt source for 4 hours:
Example Acetyl diethyl acetal Acrylic Acid Methanol 14 2.Oml Oml 18ml 1.6ml 0.4ml 18ml 16 1.2ml 0.8ml 18ml 17 l.Oml l.Oml 18ml 18 0.4ml 1.6ml 18ml 19 2.Oml* Oml 18ml Acrolein diacetoxy acetal Filter papers were dried in an oven at 70 degrees centigrade~ for 30 minutes and weighing indicated the grafting of polymer 0.8~-12.6~. (These yields were recorded after washing with methanol).

Example 20 A small cellulosic paper disk which is normally used for filtration i.e. a filter paper, about 2 cms. in diameter was immersed in a 10% solutlon of acrolein in water ~ ~ d~note5 tr~ w~ar~
:

- 15 - ~32~28 (10 ml), contained in a tube. The tube and its contents were flushed with nitrogen, sealed, and then gamma~radiated for one hour from a cobalt source (approximately 0.7 Mrad/hour). The disk was then removed and washed with water.
The following standard strains were used for testing:
a ) Staphylococcus aureus (Oxford) b) Pseudomonas ATCC
c) Candida ATCC
Dilutions were prepared in normal saline.
10ul of each bacterial solution was applied to 1 square centimetre of test filter paper. Filter papers were maintained in a moist atmosphere at room temperature for 2 hours. Filter papers werP then transferred to Sml heart brain infusion and shaken at 37 degrees centigrade for 30 minutes. 10ul was removed for sterility testing and the flasks incubated at 37 degrees centigrade for 18 hours. The flasks were inspected for growth and the growth was checked 20 on blood agar Staphylococcus Pseudomonas Candida Concentration Control Test Control Test Control Test cfu/ml (10 log) ~ ~ +
g + _ + _ +
8 + _ _ _ +
+ r -- _ +
6 + _ _ _ +
+ _ _ _ +

4 + -- _ ._ +
3 +
+ = growth -`= kill "

- 16 - 1320~28 Example 21 Whatman No. 4 filterpaper was impregnated with a solution of polyacrolein in methanol which had been polymerised by means of gamma-radiation) and dried in an oven at 70 degrees centigrade for 1 hour. The amount of impregnated polymeric antimicrobial was 9%. The impregnated filter paper was tested for antimicrobial activity and the results were recorded by comparing with a control filter-paper.
The following standard strains were used for testing:
a) Staphylococcus aureus (Oxford) b) Pseudomonas ATCC
c) Candida ATCC
Dilutions were prepared in normal saline.
10ul of each bacterial dilution was applied to 1 square centimetre of test filter paper. The filter papers were maintained in a moist atmosphere at room temperature for 2 hours. Then the filter papers were transferred to 5ml heart brain infusion and shaken at 37 degrees centigrade for -30 minutes. ~0ul was removed for sterility testing and the flasks incubated at 37 degrees centigrade for 18 hours. The flasks were inspected for growth and the growth was checked on blood agar.
Staphylococcus Pseudomonas Candida Concentration Control Test Control Test Control Test cfu/ml (10 log) + ~ r 9 + ~ + ~ -1 C
+ ~ - ~ C
7 + - - _ +
6 + - _ _ +
+ ~
4 + _ _ +
35~ 3 + _ _ _ _ _ -~ = growth - = kill C = contaminated ~ ~ .

:

- 17 - ~ 32 0 1 28 Example 22 Whatman No. 4 filterpaper was impregnated with a solution of polyacrolein. In methanol, which has been prepared by polymerising 19.3g distilled acrolein in 58 g methanol in the presence of l.O5g benzoylperoxide in a nitrogen atmosphere for 3 days at 70 degrees centigrade.
The amount of impregnated polymeric antimicrobial was 8%, The impregnated filterpaper was tested for antimicrobial activity and the results were recorded by comparing with a control filterpaper.
The following standard strains were used for testing:
a) Staphylococcus aureus (oxford) b) Pseudomonas ATCC
c) Candida ATCC
Dilutions were prepared in normal saline.
lOml of each bacterial dilution was applied to 1 square centimetre test filter paper. The filter papers were maintained in a moist atmosphere at room temperature for 2 hours. Then, the filter papers were transferred to 5ml heart brain i,nfusion and shaken at 37 degrees centigrade for 30 minutes. The flasks were incubated at 37 degrees centigrade for 18 hours, inspected for growth and the growth was checked on blood agar.
Staphylococcus Pseudomonas Candida Concentration Control Test Control Test Control Test cfu~ml (10 log) + -- ~ +
g + + _ +
8 + _ _ _ +
7 + - _ _ +

+ = growth - = kill C = contaminated _ample 23 - 18 - 1320~28 Twice, in separate experiments, cotton wool was impregnated with a solution of polyacrolein in methanol which had been prepared by polymerizing 19.3g distilled acrolein in 58g methanol in the presence of 1.05 g benzoylperoxide in a nitrogen atmosphere for 3 days at 70 degrees centigrade. The amount of impregnated, polymeric antimicrobial was 5% and 3.5~ respectively. The impregnated cottonwools were tested for antimicrobial activity and the results were recorded by comparing with control cottonwool.
The following standard strains were used for testing:
a) Staphylococcus Aureus (Oxford) b) Pseudomonas ATCC
Dilutions were prepared in normal saline.
5mg amounts of cottonwool were weighed and placed in sterile bijoux bottles. The cottonwool was saturated with 30ul of 5 different bacterial dilutions. After 2 hours at room temperature, the cottonwool was transferred to 5ml of heart brain infusion and incubated for 18 hours at 37 degrees centigrade. Cultures were inspected for growth and growth was checked by plating on blood agar.
Staphylococcus Pseudomonas Concentration Control 3.5% 5% Control 3.5~ 5%
25 Cfu/ml (10 log) + _ _ ~ _ _ 2 + _ _ +
1 ~ - - _ _ _ + = growth - = kill It will be evident that these laboratory scale examples may be extended to industrial scale processes, for example, in which the substrate cellulose, prior to incorporation in, for example, tampons, diapers or medical cellulosic products is treated with acrolein vapour or acrolein solution and is then gamma-irradiated. Further, the process may be e~tended to the continuous (as well as batch) industrial processes in which cotton, cellulosic fibre or other fibres are treated with acrolein vapours or solution prior to weaving or making into a non-woven fàbric.
Still further, the laboratory scale example may be extended to treating sheets, fabrics or cloths prior to making into clothes, drapes and other similar finished products. Still further, the example may be extended to treating the starting-materials or their final products such as ceramics, masonry, bricks, concrete, glass or plastics materials either prior to or after making these into their final fabricated forms.

Example 24 Many other substrates were treated ~ith solutions containing active polymers, for example, gauze from bandages, non-woven fabric from sanitary napkins, cottonwool from tampons - and always before microbiological testing, a control was used on the substrate which had been treated with the pure solvent ~methanol). Substrates which had been treated with the methanolic solutions of the polymers were always dried at 80 degrees centigrade/l.S hours before antimicrobial testing - and as well, extracts were made with both methanol and physiological saline to test for the presence of monomer; this was found by HPLC and GC to be less than lOppm at which the acrolein was found to be microbiologically inactive durin~ our tests:
Cotton (3.876g) with a 3~ content of polyacrolein was agitated in saline ~75ml) for 24 hours.
The saline extract was analysed by GLC (10%
carbowax 20M and on FID detector) which showed that the cotton contained less than 20ppm (the limit of detection~.
The saline extract (50ml) was added to a solution of 2,4-dinitrophenylhydrazine (O.lOOg) in 2N hydrochloric acid (25ml). The resultant solution was extracted with ~hloroform (3 x Sml). The combined organic fractions were :: ~ ~ : :

:

;, 1~20~28 then washed with 2N hydrochloric acid (2 x 5ml), water (2 x 5ml) and dried (sodium sulphate). The chloroform was evaporated to dryness and the residue dissolved in aceto-nitrile (lml). Analysis of the acetonitrile by HPLC (C18 reverse phase, 70~ aqueous mmethanol, UV detector at 245nm) showed that the cotton contained 2.4ppm of acrolein.
Typically, substrates which were found to be micro-biologically active, retained their activities after more than 6 months' standing at room temperature.
10 The following are typical and additional test-results, executed similarly to examples 20-23:
Example No. Active A~ent Staphyloccocus Pseudomonas Candida l* + +
2** + + +
3 ~ NT NT
4 + NT NT
+ NT NT
6 + NT NT
7 ~ ~ +
8 , +
9 + + +
10** + + +
11** + + +
12 + NT NT
13 NT ~ NT

1 5 + r NT NT

17 + NT NT
18 ~ NT NT
19 ~ NT NT
NT = not tested + = positive/active * (a) Tests were also carried out in phosphate buffers, ~adjusted with sodium hydroxide to give pH's of 5, :

.

132~28 6, 7, 8 and 9, respectively; results against Staphlococcus (Oxford) at levels 103 - 10a showed no differences in activities at the respective pH's.
Activities were also retained at the level of 25 ul heparinized blood or urine, respectively (both human).
(b) In another experiment, a methanolic solution was applied to spore strips of sacillus subtilis var niger and left in contact at room temperature for 2 hours before transferring to heart brain infusion for 18 hours/37 degrees centigrade. The cultures were inspected for growth and plated to blood agar ~ the solution of polymer being active against the spores, whilst the methanol-solvent was inactive under these conditions.
(c) In separate experiments, 0.1g of cotton wool which had been coated with the polymer, was aseptically weighed into separate sterile bijoux bottles. The cotton wool was then incubated with 0.5ml of dilu~ions of cultures of Erwinia carotovora (Important in soft rot of potatoes or cabbages), S.Aureus (important regarding bovine mastilis) and Salmonella dublin (important regarding bovine calf mortality), respectively. These were left at room temperature for 2 hours and then the cotton wool was transferred to TSB, an enriched nutrient broth and incubated at 32 deg~ees centigrade, 37 degrees centigrade and 37 degrees centigrade, respectively.
The coating on the respective cotton wools killed the 3 organisms respectively, in the range I05-lG7/ml of pathogens.
(d) In separate and similar experiments ~except the ~media used was malt extract bro~h, Sabouraud 35~ ~ dextrose agar, 0.1% peptone water as diluent), kills were achieved in the range 10~-105/ml of ~ ~; Aureobasidium pu~llurans (associated with : : :

, - 22 - ~320128 black-slime on bathroom tiles and groutings) and Pycnoporus coccineus (associated with rotting in timbers).
(et In 3 separate expeximents, tests were also conducted for anti-viral activities and found active in each case, using the following method for Herpes Simplex, Enterovirus, Echo 11 and Influenza PR8, respectively: a 104/ml suspension of the viral partlcles was applied to cottonwool treated with the antimocrobial polymer, followed by centrifugation. 0.1 ml aliquots of the centrifugate were introduced into cultures of human embryonic fibroblasts or HeLa cells and the cytopathic effect noted.
** Also active in a preservative test conducted over 14 days at pH 7.5 in glycerol-triethanolamine buffer, against Pseudomonas ATCC dilutions prepared in normal saline.
.
"Staphylococcus", Pseudomonas" and "Candida" referred to herein are more specificically identified as:
20 . Staphlycoccus aureus NCTC 6571 Pseudomonas aeruginosa ATCC 27853 . Candida albicans PMH 82/312 .

.

Claims

1. A process for rendering matter biocidal or biostatic, which process comprises applying to or incorporating in the matter a biocidally or biostatlcally effective amount of a polymer compound having the polymeric unit ;

or this unit is hydrated, hemi-acetal or acetal form of the formulae (a) (b) (c) (d) (e) (f) wherein R is hydrogen and x is an integer of 1 or more; or a composition containing said polymeric compound.

2. A process as claimed in claim 1, wherein the composition containing said polymeric compound is selected from the group comprising compositions in the form of a solid, liquid, solution, gel, emulsion and suspension.

3. A process as claimed in claim 1, wherein the matter is selected from the group comprising water, water-containing compositions, food, cosmetics, toiletries, pharmaceuticals, oil or lubricants, cellulose, modified cellulose, regenerated cellulose, rayon, polymers of plastic materials, rubbers, ceramics, glass, silica, concrete, masonry and minerals.

4. A process as claimed in claim 2, wherein the matter is selected from the group comprising water, water-containing compositions, food, cosmetics, toiletries, pharmaceuticals, oil or lubricants, cellulose, modified cellulose, regenerated cellulose, rayon, polymers of plastic materials, rubbers, ceramics, glass, silica, concrete, masonry and minerals.

5. A process as claimed in claim 3, wherein the polymers of plastic materials are selected from the group comprising vinyl polymers, acrylic polymers or polyesters.

6. A process as claimed in claim 4, wherein the polymers of plastic materials are selected from the group comprising vinyl polymers, acrylic polymers and polyesters.

7. A process as claimed in claim 1, wherein the matter is selected from the group comprising matter in the form of airconditioner filters, aprons, bags for laundry, bandages, tiles or grout, bricks, carpets, catheters or other related hospital instruments made from plastic or glass, clothing, food wraps, concrete, cottonballs or cotton tips, diapers, drapes, disposable cardboard or plastic food boxes, face masks, bed covers, inners of shoes, ironing board covers, nursing pads, paint, paper plates and cups, water reservoirs or swimming pool or water-treatment chemicals, rubbish bins, sanitary napkins or feminine hygiene tampons, shelving paper, shower curtains, teatowels, telephones, tents, tissues handkerchiefs, toilet paper, toothbrushes, towels, wall paper, window awnings or other like structures made from canvas or plastic, wipes, mops, sponges, wood and wood-impregnants.

8. A process as claimed in claim 2, wherein the matter is selected from the group comprising matter in the form of airconditioner filters, aprons, bags for laundry, bandages, tiles or grout, bricks, carpets, catheters or other related hospital instruments made from plastic or glass, clothing, food wraps, concrete, cottonballs or cotton tips, diapers, drapes, disposable cardboard or plastic food boxes, face masks, bed covers, inners of shoes, ironing board covers, nursing pads, paint, paper plates and cups, water reservoirs or swimming pool or water-treatment chemicals, rubbish bins, sanitary napkins or feminine hygiene tampons, shelving paper, shower curtains, teatowels, telephones, tents, tissues handkerchiefs, toilet paper, toothbrushes, towels, wall paper, window awnings or other like structures made from canvas or plastic, wipes, mops, sponges, wood and wood-impregnants.