CA1037442A - Liquid-dispensing nozzle assembly - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

An improved liquid-dispensing nozzle and more specifically, an improved vapor recovery means for a nozzle comprising a vapor collector (such as a flexible bellows) surrounding a portion of the discharge spout in spaced relation thereto, one end of which is sealed to the upper portion of the spout; and at the other end of the vapor collector, a compressible cellular plastic material such as foamed plastic associated therewith. When the discharge spout is inserted into, e.g., an automobile fillpipe, the compressible cellular plastic material forms a vapor seal with the upper end of the fillpipe whereby the vapors escaping from the fillpipe are directed into the interior chamber formed between the exterior of the discharge spout and the inside of the vapor collector thereby minimizing the escape of vapors to the atmosphere. The vapors are then removed from this chamber. The compressible cellular plastic material may be made from an elastomer selected from the group consisting of (1) polyacrylate elastomer, (2) acrylonitrile containing elastomer, (3) epoxy derived elastomer and (4) fluorine containing elastomer.

Description

: 1~?37~4~ i The present invention relates to a nozzle for dispensing ;~ a liquid, and more particularly to a nozzle having means for preventing the escape of vapors during a liquid dispensing operation.
~; Normally, as a fuel such as gasoline is being supplied ~i;
,;, ~ .: . .
through a fuel-dispensing nozzle to, for example, an automobile ~;` ;
! fuel tank, fuel vapor escapes from the fuel tank fillpipe, this vapor of course adding to the already pressing air pollution ~`
1, :'~ ':'.' ,~"
;i problem. Such air pollution is increasingly becoming a cause of ~; lO concern and numerous governmental jurisdictions are requiring con-trol of causes of air pollution. An increasing number of juris-dictions are requiring minimization of escape of both li~uid uel and fuel vapor from vehicles which are being supplied with uel.
Reducing the fuel delivery rate, while reducing liquid-splash~back, does not prevent escape of vapors and in act, because of the ~,~ longer time required to ill the vehicle fuel tank, may increase the escape of fuel vapors lost during the filling of the tank.
The prior art~has suggested various means o recovering vapors which otherwise would escape to the atmosphere while fuel tanks are being~filIed. For example, U.S. Patent No. 3,581,782 ~J ~ dis~closes~a vapor emission~control~system sultable for gasoline and other fuel delivery systems, and adapted to eliminate the escape of fuel vapors to the atmosphere. The disclosed embodiment of~the control system includes, for example, a flexible annular sleeve surrounding the spout of the nozzle and ~ealed to the fill-pipe of the fuel tank by means o an expandible member whichj when i~
expanded after the spout is inoerted into the illpipe, prevents ~ the emission of~vapor to the atmosphere.
¦~ Similarly, U.S. Patent No. 3,566,928 discloses a vapor ~l 30 seal for fuel dispensing nozzles wherein the orward end ~i.e., l`~
;l~ the end opposite the main housing of the nozzle) of the flexible ~i,,:, ,.. : . ~

1~37~Z
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bellows which surrounds the spout is sealed to the ~illpipe by ~i~
means of an annular-shaped magnetic rubber sealing assembly.
It is known also in tha prior art simply to employ a flexible means surrounding the spout, such as the flexible bellows ;
~.
by itself. In this case, when the discharge spout is inserted into the fillpipe, the flexible bellows is compressed and tends to seal itself to the upper portion of the fillpipe. However, this , . .
seal between the forward or heel portion of the bellows and the upper portion of the fillpipe is not a good one, and hence the i~ 10 above-noted prior art suggestion for using magnetic rubber means.
',t,Zl~; Reerence is also made to U.S. Patent Nos. 2,850,049 and ,, 2~908,299 for fuel vapor recovery systems.
`~ There i5 therefore a need for a simple and effeative 1 device for sealing a vapor aolleation device to the upper portion i of, for example, an automobile illpipe. Specifically, there is a need for improving the seal that is possible between, for example, ; the flexible bellows o~ the prior art and the upper portion o an automobile fuel tank fillpipe. ;
It is therefore a primary object of the present invention to provide a liquld-dlspensing nozzle provided with vapor recovery means. -It is a further object of the present invention to provide~a liquid~fuel-dispensing nozzle wherein the seal between the vapor collecting means and the automobile fuel tank fillpipe ~¦~ is improved.
It is yet a further object o~ the present invention to provide such an improved sealing means which is simple in design.
Other objects and advantages will become apparent to il those skilled in the art from the ensuing description.

i 30 ~he present invention accomplishes the above objects and .~. j ..
i others by utilizing, in conjunction with a vapor collector means .;:j , i , . .

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(such as flexible bellows) which surround a portion of the dis- I
~ charge spout of a liquid fuel-dispensing nozzle, a compressible r ; cellular plastic material such as foamed plastic mounted on the ~ -~
.: .. , ~ forward or heel portion thereof to engage the upper portion of, ~
:
for example, the automobile fuel tank fillpipe. Tbe use o the '.!.'';'''' ~',.
compressible cellular plastic material provides a greatly improved ;;
seal between the vapor collector means, preferably a flexible bellows, and the fillpipe compared to khe use of the vapor collector alone ~-Figure 1 is a side view, partly in cross-section, of the improved fuel-dispensing nozzle of the present invention.
. ~ . ..
Figure 2 is an enlarged view, partly in cross-section, of the improved liquid fuel-dispensing nozzle o the pre~ent invention inserked into a fillpipe of an automobile ~uel tank.
"
The improved vapor reaovery Apparatus o~ the present invention is particularly useful with conventional liquid fuel-:, .. .
dispensing nozzles, and while the present invention is applicable to all liquid-dispensing nozzles, it is particularly useful with liquid fuel ~e.g., gasoline) nozzles, and the present invention .~ .
20 will therefore be described~with reference to the latter, although ;
~ those skilled in the art will realize that the invention generally'':s'', ,~ ~19 applicable to ~a much broader field. r ~' ~i ~; A liquid fuel-dispensing nozzle comprises a main body ; or housing having an integral handle, a fuel inlet which normally comprises a flexible conduit means communicating between the source of fuel such as an underground storage tank, and a discharge spout which is adapted for insertion into the fillpipe of the fuel tank.
A spring means is usually provided around a major portion of the discharge spout. The sprlng means assists in holding the spout in ~;¦ 30 the fillpipe during the filling operation, especially during self- ~
'il serve operations. ` -~1 ~,.; j `i -3-. ~ ...................................................................... . ..... .
,;~ ;. '.. : :.: ' ~374~2 As pointed out above, the prior art has suggested that a vapor collecting device, such as a flexible bellows, be employed to surround a major portion of the discharge spout. The bellows ~ . .. . . .
is sealed to the housing at the upper end of the spout and terminates in a heel-portion which is annular in shape and has a flat face for contacting the upper portion of the fillpipe. As , the spout is inserted into the fillpipe, the bellows is compressed and the flat face of the heel portion forms a seal with the upper portion of the fillpipe.
According to the present invention, a compressible cellular plastic material, such as a foamed synthetic resin `
; cellular plastic, is carried by or secured to the flat-faced heel .;
portion o khe bellows and it is this compressible cellular plastic material which contacts the ~illpipe. It has been found that ~uah !''"'' material greatly improves the seal between the flexible bellows . ", . .
~i! and the fillpipe and improves the reduction in the amount of vapors .; . , escaping to the atmosphere. Suitable means is provided for remov- ~ ~, ing the vapors from the interior of the bellows, as is conventional.
Referring now to Figure 1, a typical~gasoline-dispensing ~
nozzle is~ shown whlch is provided with vapor recovery means. More ~ ~ -apecificallyj a nozz1e generally designated 10 comprises a main ;~
~ body or housing ll, an inlet conduit 12 and a discharge spout 13.
`~; A handle 14 lS provided for actuating the delivery of gasoline or other liquid fuel ~ In addition, and as is conventional, a retainer means 15 is also provided on the main body of the housing for ~ holding the handle 14 in its fuel-delivery position. It is also '"'I
;`¦ conventional to provide suah nozzles with means or automatically . ~
!"`~ shutting off delivery of fuel when the fuel tank or fillpipe is full. Such means are not shown in Figure 1, but may include an orifice near the discharge outlet of the spout 13, and a tube . .~
1l communicating from the orifice to a control mechanism within the ~ :
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main body 11 of the nozzle, wherein the control mechanism, sensing ,,~ ,.: ,~ :
the presence of a gas or liquid near the orifice, acts to dis~
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engage handle 14 from retainer 15 thereby automatically stopping delivery of fuel through the nozzle. ~;
The major portion of spout 13 is surrounded by a ~lexible vapor collector which may take the form of a flexible bellows 17. ~ ~;
The upper end 19 of bellows 17 is sealed to surface 18 of tapered ;-portion 16 of the nozzle. The opposite end of bellows 17 com-prises a heel portion 21 having a flat face 21' and, according to i-the present invention, a compressible cellular plastic material 22 is carried by or secured to face 21' of heel portion 21. Both ;, ,, : .
heel portion 21 and compressible;cellular plastic materiaL 22 are ` ;
substantially annular in shape providing a space 23 between the . same and the outside surface o~ spout 13, allowing vapors esaaping , i from the fillpipe to pass therebetween and into the interior o~ ;

bellows 17. An aperture 20 is conveniently provided near the upper ~.,}:
,~l end of the bellows 17 for removal of vapors. The means for remov~
ing the vapors rom aperture 20 is not per se included within the scope of the present invention, but may comprise, for example, a flexible tubing attached to aperture 20, the flexible tubing communicating with,~for example, a combustion means whereby the vapors may be rendered harmless. Alternatively, the hydrocarbons :. . i~ : ., .
~ in the vapors may~be recovered by other suitable means such as by ', . ?~
adsorptionr or condensation.
Face 24 of compressible cellular plastic material 22 is the surface which contacts the fillpipe, referenae now being made to Figure 2 which shows the nozzle of the present invention inserted into a fillpipe. More specifically, referring to Figure ~` 2, spout 13 is shown inserted into a fillpipe 25, the upper por-`l 30 tion of the latter aontacting faae 24 of compressible cellular ;, plastic material 22 thereby sealing the same against vapor ; `~
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~, escape. The spout 13 is shown as being provided with a spring `
means 26 which assists in maintaining the spout in the fillpipe `~
during the filling operation. The spring 26 is preferably of square cross-section although a round spring is satisactory. In . .
operation, as the spout is inserted into the fillpipe, the spring means acts to ratain the same therein. As the spout 13 is forced `
into the illpipe, the bellow 17 is compressed and as the spout is held therein by means o the spring 26, face 24 of compressible ~:
cellular plastic material 22 tightly seals the fillpipe against possible vapor loss. Vapors which leave fillpipe 25 pass through ; space 23 into the interior o bellows 17 rom which they are removed through aperture 20 (see Figure 1).
The compressible cellular plastic material may be secured `
to the heel portion 21 o the bellows by any suitable means, or . ., .~ .
examplej an epoxy-type cement can be employed for this purpose, 'l but those skilled in the art will realize that~any adhesive means ~.''1 . . .
i~ may be employed for this purpose. O course, the 1exible bellows ~ and compressible cellular plastic material must be formed o : ,;.
materials which are substantially resistant to the fuel liquid ;~i 20 and vapor being dispensed. For example, the bellows may be ;,,'J. ` aomprL~sed of a flexlble polychloroprene rubber (i.e., neoprene), I such bellows being commercially available. The compressible cellular plasti~c is deined as a cellular plastic material which iq c mpressible under a normal load ~in psi.) obtained when the t~ I compressible cellular plastic contacts the fillpipe during the dispensing of uel. The term "compressible" is used in its normal dictionary sense and includes materials which deorm to a certain ... , ~ :
, extent w~en the spout o the nozzle is inserted into the fillpipe, ` thereby providing an extremely good seal against vapor escape.
~ .
Typically, the aompressible cellular plastic material is compressed under such normal load in the range o rom about 5 to about 85~, . . , ; ~, 1l -6~
.' '', ' .
. . .

4~z ", ~.`.,.. :, more preferably from about 25 to about 70% based upon the original volume of material. Typically, examples of the compressible , ~ .
cellular plastic material are the cellular material (i.e., foams) obtained from polychloroprene latex, polyethylene, silicone, ~ i urethane polymer, poly~vinyl chloride), polytetrafluoroethylene, ;
cellulose acetopropianate, and urea-~ormaldehyde resin. Particu- ;
larly preferred compressible cellular plastic materials are poly- !;,;',,~
urethane foam and polychloroprene latex foam. As stated above, such compressible cellular plastic material should be substantially resistant towards the fuel liquid being dispensed and the corres-ponding vapor, particularly when such fuel is gasoline.
The exposed face of the compressible cellular plastic :',, ! ', material can be aoaked with the same plastic material used to `
form the cellular plastic material. Thus, the face can have a surface skin or coating which contacts the receiver inlet to which liquid is being dispensed. In addition, the face of the compressible cellular plastic material can have a surface skin or ;.; ;
coating which is of a diferent material such as a synthetic resinous material or a natural occurring materialj both of which are substant1ally~resistant to fuel liquid and vapor being dispensed. The coating material, either the same or different from the compresslble~cellular plastic material, has to be resllient, that is, the material deforms to a certain extent when the spout of the nozzle is inserted into the fuel pipe. Typical examples of resilient material are leather and synthetic resin such as polychloroprene (neoprene). It is contemplated within the scope of this invention that the term "compressible cellular plastic material" includes such coating or different resilient material affixed thereto to form the exposed face seal.
.; .,~ ,,: . . , ~ 30 The thickness of the compressible cellular plastic ~;
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1 material is not critical, and may vary from a minimum thickness ~
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- required to provide the minimum seal to a maximum thickness which would be dictated by economic considerations (i.e., an extremely ; thick material would not be reguired). Typicallyl the compressible '' cellular plastic material is utilized in a thickness which may ` ' -range from about 1/16 inch to about 1/2 inch. ' ' ' The invention can be better appreciated by the following ''~ non-limiting examples:
": .
; EXAMPLE I ~.
An OPW #7 vapor recovery gasoline dispensing no~zle was .,. ~ ;
equipped with a polychloroprene bellows boot, one end of which was , - .
'; attached to the nozzle housing, the other end surrounding the `
.,~ . .nozzle outlet having only an exposed plain surface. The bellows ' ' boot was substantially of the same geometrical configuration as :'' ''l the boot set forth in Figure I. The second nozzle, as above, was equipped with an identi~al bellows boot except that the face con-' tained a closed cell polychloroprene oam of approximately 1/4 ''l inch thickness. The cars were tested for percent hydrocarbon recovery at ambient conditions of temperature. The following table lists the percent hydrocarbon recovery utilizing the above nozzles. ~ '... ;, .
1: 2 0 TABLE
,.~,,~ - `, 'l~ Type of Nozzle ~ No. of Cars Tested % Hydrocarbon Recovery PW #7 86 65%
`; Plain Face OPW #7 ~150 82% 2 Foam Face A round cross-section retention spring was used ~or i maintaining the dispensing nozzle in position.
;, ~ 2 A square cross-section retention spring was used for `;, maintaining the dispensing nozzle in posikion.
. .
; 3~ 30 EXAMPLE II
: ~ I .
A modified OPW ~7 vapor recovery nozzle was equipped ' with a polychloroprene bellows boot one end of whiah was attached to the nozzle housing, the other end surrounding the nozzle outlet .. ,;;-, .
, ,, ., ~ ..
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': . ;
., I , having a surface face. The modification of the nozzle was the :
inclusion of a 3/4 inch vapor return line on the bottom of the handle area. A square cross-section retention spring was used on ' the spout. The bellows boot was substantially the same geometrical .~--configuration as the boot set forth in Figure I. The surface of the first boot was modified by affixing a unidirectional magnet ' to the boot surface. The magnet was further modified by the bond-ing o an outer leather surface to the magnet. i `
A second boot was modified the same as the first boot 1 ~ lO except that a closed cell urethane foam having a thickness of 1/8 : inch was affixed to the unidirectional magnet. The leather surface ; ,..................................................................... . ... , `
was then affixed to the closed cell ureth le foam. ~Z
The above gasoline nozzles were evaluated in a typical ~
service station environment at ambient temperatures. Table II ~ ;
.. . ... .
: lists the results obtained ~rom the evaluation of these gasoline l nozzles.
,i., ~;~ TABLE II
,, ~ Type of Nozzle No. of Cars Tested % Hydrocarbon Recovery j j , . .
;l OPW ~7 + 12 92.2%
l 20 magnet +
;~ leather ., ~ ,. .
OPW #7 + 13 97.6%
magnet +
' urethane foam +
leather ;, . ..
The previous examples demonstrate the outstanding recovery -~
of hydrocarbon vapor using the improved vapor recovery apparatus of this invention. More particularly, the comparative results set : ,.; ., ,::
~I forth in Examples I and II demonstrate the contribution o~ the `,, 30 compressible cellular plastic material in substantially preventing `

; the escape of hydrocarbon vapor during the dispensing of fuel to a ;

motor vehicle~ The increase in percent recovery with the com- ~
:., ~. . , pressible cellular plastic material is particularly relevant where ~
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high hydrocarbon recoveries are required due to environmental ,. :: .
~ regulations. ~
: .
The improved vapor sealing means of the present ~!,' ' : invention can be employed with any liquid-dispensing nozzle. `c ....
Although the system of the present invention has been disclosed ~
,: , with reference to a fuel delivery system, particularly a gasoline :
. delivery system, the nozzle assembly of the present invention can be used to prevent escape of vapors in systems for the delivery of liquids other than fuels. Accordingly, it is seen -~
that in accordance with the present invention a nozzle assembly x ,.. . .
, is provided for the delivery of li~uids and including means for ' substantially preventing escape to the atmosphere o vapor during such delivery.
While this invention has been described with respect to various specific examples and embodiments, it is to be '1 understood that the invention is not limited thereto and that `~ ;
it can be variously practiced within the scope of the following claims.
SUPPLEMENTARY-DISCLOSURE
It has further been found that a particularly preferred compressible cellular plastic material having improved resistance ` to abrasion and the ability to conform to a fillpipe is an ~--' elastomer, selected from the group consisting of (I) polyacrylate `
elastomer, (II) acrylonitrile containing elastomer, (III) epoxy derived elastomer and (IV) fluorine containing elastomer. Each : ;! -of these elastomer materials is more particularly described ~¦ below.
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I I. Polyacrylate Elastomer .~ The polyacrylate elastomers which can be used for ,,, ~. .
forming the co~pressible cellular material are those elastomers ;
which comprise at least about 50 wt. percent of polymerization ?j"
units derived from an alkyl acrylate or mixtures thereof, wherein ~;
.
the alkyl portion has from about 1 to about 6 carbon atoms.
Typical examples of alkyl groups are methyl, ethyll propyl and butyl. ~he alkyl acrylate monomer or mixtures thereof is more ........................................................................... .. .
preferably present in the elastomers in a wt. percent of at least about 70 and still more preferably at least about 90. In a ,.::, ,i:': ::
' still more preferred embodiment of this invention, the polyacrylate elastomers are derived from ethyl acrylate preferably within the weight percentage ranges as set forth above.
The polyacrylate elastomers utilized in forming the compressible cellular material are vulcanized and/or cured and the cellular structure formed using materials and process I conditions which are typical for polyacrylate elastomers. The ` `~
materials and conditions utilized are chosen in order to provide '~.. 1 j . , a compressible cellular material which has performance characteristics as set forth herein. ;-~
It will be understood for the purposes of this specification that the term polyacrylate elastomers is used in a generic sense to include homopolymers, copolymers, terpolymers ~i s~
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Qr~ other interpolymers which have molecular weights of at least ; about 75,000, more preferably from about 100,000 to about 3,000,000 and still more preferably from about 250,000 to about 1,500,000.
The various copolymerizable monomers as set forth below can ~;~
vary widely but should not materially deteriorate t'ne polyacrylate cellular material in hydrocarbon resistance, abrasion resistance and performance characteristics as set forth herein.
The alkyl acrylate monomer is usually polymerized by ree radical polymerization technique ~also known as the addition poly-merization technique). Such technique consists of contacting the . . ~ ~, . .
monomer(s) with polymerization initiator either in the absence or presence of a diluent at a temperature usually between 0 and ~00C.
The polymerization initiator is a substance capable af liberating a free radical under the conditions of polymerizationr e.g., benzoy~
peroxide, tert-butyl hydroperoxide, cumyl peroxide, postassium per~ulfate, acetyl peroxide, hydrogen peroxide, axobisisobutyronitxile,~
i or perbenzoic acid. For reasons of economy, benzoyl peroxide or axobisisobutyronitrile are most commonly used.
The acrylate monomer may also be polymerized or copoly-~0 meriæed using an anionic initiator such as naphtylsodium or . .
butyllithium in tetrahydrofuran solution or sodium metal in liquid --ammonia solution.
The polyme~ization of the alkyl acrylate monomer may also . . ~ , ..
be effected by other polymerization techniques such as by the use of Ziegler type catalysts, gamma ray irradiation, or thermal techniques.
:, :
i~ The diluent for the polymerization mixture may be either , . ;

~ an inert sol~ent such as benzene, toluene, xylene, cyclohexane, , hexane, naphtha, tetrahydrouran, white oil, or dodecane; or a non-solvent such as water or liquid ammonia. Thus, the polymerization can be carried out in bul~, solution, emulsion, or suspension.
The temperature for the polymerization depends on the catalyst system employed and to some extent upon the nature of the monomers to be polymerized. Thus, the copolymerization of an ;.
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1~37442 ` acrylate monomer with a very reactive compound may be catalyzed at ;
; temperatures from about -100 to S0C., pre~erably at -70 to 0C. -~
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On the other hand, the optimum temperature for ef~ecting the free radical catalyzed homopolymerization of an acrylate monomer is ;
usually from 0~ to l00C., preferably 30 to 80C. Similarly, the `
optimum temperatures for effecting the free radical catalyzed interpolymerization of for example ethyl acrylate with one or more polymerizable comonomers will vary according to the reactivity of these other comonomers. In most instances such temperatures like- ~
wise are within the range from about 0 to 100C. `~ 1 A large variety of comonomers can be used to ~orm `;
polymers with one or more alkyl acrylate monomers. For the most part, such monomers are polymerizable vinyl monomer9. They include, for example: (l) esters of unsaturated alcohols, ~2) esters o~
unsaturated acids, ~3) vinyl cyclic compounds, ~4) unsaturated ~" "~
~ ethers, tS) unsaturated ketones, ~6) unsaturated amides, (7) ~
: ,: , .
;;j un5aturated aliphatic hydrocarbons, (8) vinyl halides, ~9) esters ;~ ;
o~ unsaturated polyhdric alcohols (e.g., butenediol), (l0) unsat-; urated acids, (ll) unsaturated acid anhydrides, 112) unsaturated ~
20 acid chlorides, and (13) unsaturated nitriles. -. . , ~ , . - .
Specific illustrations of such compounds are: `
Esters of unsaturated alcohols, i.e., allyl, ; ~-_ methallyl crotyl,~;L-chloroallyl, 2-chloroallyl, cinnamyl, vinyl, methyl-vinyl, l-phenallyl, butenyl, etc., and ~a) saturated acids ,. . . . .
such as for instance, acetic, propionic, buyric, valeric, caproic, l~ stearic, etc.; (b) unsaturated acids such as acrylic alpha-sub-`, sitltuted acryllc ~including alkacrylic, e.g., methacrylic, ethylacrylic, propylacrylic, etc.), crontonic, oleic, linoleic, linolenic, etc., ~c) polybasic acids such as oxalic, malonic, i"'~, l .' Ij~ 30 succinic, glutaric, adipic, pimelic, suber~c, azelaic, sebacic, .. , . ;~
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- etc., td) unsaturated polybasic acids such as maleic, furmaric, citraconic, mesaconic, itaconic, methylenemalonic, acetylene-... . . .
dicarbonzylic aconitic, etc., (e) aromatic acids, e.g., benzoic, phenylacetic, phthalic, terephthalic, benzolyphthalic, etc.
. ,.~ , .
, . 20 The esters of saturated alcohols such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl,

2-ethylhexyl, cyclohexyl, benzyl, etc., with unsaturated aliphatic monobasic and polybasic acids, examples o~ which are illustrated ^
above.

3. Esters of unsaturated polyhydric alcohols, e.g., butenediol, etc., with saturated and unsaturated aliphatic and aromatic, monobasic and polybasic acids, illustrative examples of which appear above.
~ , Vinyl cyclic compounds including (a) monovinyl aromatic hydrocarbons, e~g., styrene, o-,m-, p-chlorostyrenes, ; -bromostyrenes, -fluorostyrenes, -methylstyrenes, -ethylstyrenes, -cyanostyrenes, do-, tri- and tetra-, etc., -chlorostyrenes, -bromostyrenes, -flurostyrenes, -methylstyrenes, .,~ . ;.
-ethylstyrenes, -cyanostyrenes, vinylcyclohexane, vinylfuran, ;
20 ~vinylpyridine, vinyl~enzofuran, divinybenzene, trivinylbenzene, v allybenzene, N-vinyl~carbazole, N-vinylpyrrolidone, N-vinyloxa-zolidone, etc. ;
. U~saturated ethers such as, e.g., methyl vinyl .
ether, ethyl vinyl ether, cyclohexyl vinyl ether; octyl vinyl ether, diallylether,~allyl ethyl ether, etc.
6. Unsaturated ketones~ e.g., methyl vinyl ketone, . ~ . .
~1 ~thyl vinyl ketone, etc.
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7. Unsaturated amides, such as acrylamide, N-methylacrylamide, N-phenylacrylamide, N-allylacrylamide, 1 30 N methylolacrylamide, N-allycaprolactam, etc.
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8. Unsaturated aliphatic hydrocarbons, for ` instance, ethylene, propylene, butenes, butadiene, isoprene, : . , 2-chlorobutadiene, alpha-olefins, e~c.
9. Vinyl halides, e.g., vinyl fluorice, vinyl ; chloride, vinyl bromide, binyl iodine, vinylidene chloride, vinyli-, , ~,-:, ..
dene bromide, allyl chloride, allyl bromide, etc.
1~. Unsaturated acid anhydrides, e.g~, maleic, ;: .
citraconic, propylacrylic, etc., examples of which appear above.
11. Unsaturated acid anhydrides, e.g., maleic, . . . . .
10 citraconic, itaconic, cis-4-cyclohexene-1, 2-dicarboxylic, ; :
bicyclo ~2.2.1) 5-heptene-2, 3-dicarboxylic, etc.
~` 12. Unsaturated acid halides such as cinnamoyl, acrylyl, methacrylyl, crontonyl, oleyl, umaryl, ~tc. ;~
13. Unsaturated nitriles, e.~., acrylonitrile, j~ `;
methacrylonitrile and other substituted acrylonitxiles. ;
~- The polyalkylacrylate elastome~s, many of which can ~
i,.~ . .
:' be classified as rubber, æe usually black, but pale shades are ..... . .
i possible if a siliceous iller is used. Despite the act that ; it has little unsaturation, it may be readily vulcanized by 20 polyaminies. Particularly useful amines are polyalkylene amines wherein the~alkylene portion has from 1 to 2 carbon atoms. In general from 2 to about 6 amino groups are present in the poly-amines. Sulphur acts as~an 'lanti-ager" rather than as a curing agent. In addition to sulphur, lead phosphite (D~phos) can be used to improve heat reslstance. Typical amines include:
1. Trimene base Z ~ 2. Triethylene tetramine 3. Hexamethylene diamine carSamate The last componant ~3) can provide for better , ;
30 processing and a mix which may be stocked for reasonable periods i `.. , .;
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without showing l'set-up". Examples of curing systems (parts by weight per 100 parts polymer) are shown below. .
Best heat ag hg Trimene base 3-0 ~ . . .
Sulphur 0-5 : .:
Low compression set. Useful for white stocks :.
' Triethylene tetramine 1-5 , .
~ Benzthiazyl disulphie 2-0 " ;:, As reinforcing pigments, SAF, FEF, and HAF blacks are prefereable to Channel black, which retards cure, while Silene EF and HiSil ~; silicas may be used for light colour compounds. A particularly preferred polyalkylacrylate elastomer is a copolymer comprising i, about 95% ethylacrylate and about 5% chloroethyl vinyl ether. ' 7"'l This particular elastomer is e~pecially suitable ~or forming the , compressible cellular material.
" .
;5 As stated above the formation of the cellular ; structure and the vulcanization and/or curing are adjusted in order to prepare a cellular material having the compressibility and physical characteristics as set forth herein. For method of `
preparing the cellular structure see the following references:
.1 H.J. Stern, Rubber: Natural and Synthetic, 2nd. Ed., Palmerton Publishing Co., N.Y., 1967, pp. 360-365; The Vanderbilt Rubber ~ ~ Handbook, R T. Vanderbilt Co., Inc., N.Y., 1958, pp. 463-4, Y~ 478-9, 486; and W.J.S.Naunton, Ed., The Applied Science of Rubber, 1 Edward Arnol~l ~Publishexs) Ltd. London, 1961. While either an open cell or closed cell structure is suitable, a predominantly ,~, , ,: .
closed cell structure is preferred.

~3 ; ., 1 : . ~ , .
;~ 30 ~ -16-:.. j . . .
, ,-`, .
, ~,i :: ;:

~,. " . ~
~;I` j`

~03744Z : ~
II. Acrylonitrile Containing Elastomers `
The acrylonitrile containing elastomers which can be ~ used for forming thq compressible cellular material are those lr-;~ elastomers which comprise at least about 5 wt. percent of poly-merization units derived from acrylonitrile. The acrylonitrile ~ ;
monomer is more preferably present in the elastomers in a wt. `~
percent of from about 18 to about 40 and still more preerably ;; ;~
.. ~ .. ....
~ from about 25 to about 30. In a still more preferred embodiment ,....................................................................... ~,. ..
of this invention, the acrylonitrile containing elastomers are ~`
10 polymerized with olefinic comonomers within the weight percentage ;~ -,~,,: . ~. ..
ranges as set forth above, more preferably 1,3,diolefins, and still ~
more preferably 1,3,butadiene. `;`
The acrylonitrile containing elastomers utilized in forming the compressible cellular material are vulcanized and/or cured and the cellular strUcture orm~d using materials and !~, process conditions which are typical for acrylonitrile containing 'A elastomers. The materials and conditions utilized are chosen ' in order to provide a compressible cellular material which has ~:~;! performance characteristics as set forth hérein. !"'~
It will be understood for the purposes of this , specifica~tion that the term acrylonitrile containing elastomers is used in a generic sense to include homopolymers, copolymers, terpolymers and other;interpo~lymers which have molecular weights of at~least about SO,OOO,;more preferably from about 100,000 ?~
to about 3,~000,000.~ The;~varlous oopolymerizable monomers as i ; `
set ~orth below can~vary widely but should not materially deteriorate the acrylonitrile containing cellular material .... ..
., ~, . . . .
~ 17-.~, : .~ ,.. :
,i;~;; j ~ : :

, ~ li , '~ ' 1`, . , ~,: . . .

in hydrocarbon resistance, abrasion resistance and performance characteristics as set forth herein.
.. . ~,~ .
~ .
The acrylonitrile monomer is usually polymerized by ; free radical polymerization technique (also known as the addition polymerization technique). Such techniaue consists of contacting the monomer(s) with polymerization initiator either in the ahsence .. .. .
or presence of a diluent at a temperature usuall~ between 0 and , " 200C. The polymerization initiator is a substance capable of liberating a free radical under the conditions of polymerization, -~
10 e.g., benzoyl peroxide, tert-butyl hydroperoxide, cumyl peroxide, postassium persulrate, acetyl peroxide, hydrogen peroxide, axobisisobutyronitrile, or perbenzoic acid. For reasons of economy, benzoyl peroxide or axobisisobutyronitrile are most commonly used.
; The acrylon~trile monomer may also be polymeriæed or copolymerized using an anionic initiator such as naphtylsodium or butyllithium in tetrahydxofuran solution or soaium metal in liquid ammonia solution. ,;i s, , .
The polymerization of the acrylonitrile monomer may 20 also be effected by other polymerization techniques such as by~the use of ~iegler~type~oatalysts, gamma ray irradiation, or thermal techniques.
The diluent for the polymerization mixture may be E.
either an inert;~solvent such as benzene, toluene, xylene, cyclo-hexane, hexanej-naphtha, tetrahydrofuran, white oil, or dodecane; ;~
or a non-solvent suoh as water or liquid ammonia. Thus, the poly-meri~ation can be carried out in ~ulk, solution, emulsion, or ;~
suspension.
~` The temperature for the polymerization depends on the :....................................................................... ,~'::, .'` ', ~j 30 catalyst system employed and to some extent upon the nature of ,: , , the monomers to be polymerized. Thus, the copolymerization ~
~ .. , . . . .: .
,, ., :
' "' ' ~' ~ .:' .t " ~ -18- ~ ;

3744Z ~-an acrylonitrile monomer with a very reactive compound may be catalyzed at temperatures from about -100 to 50C., preferably at -70 to 0C. On the other hand, the optimumi temperature for effecting the free radical catalyzed homopolymerization of an ;
- acrylonitrile monomer is usually from 0 to 100C., preferably ~l , . . . .
- 30 to 80C. Similarly, the optimumi temperatures for efrecting the free radical catalyzed interpolymerization o~ acrylonitrile s with one or more polymerizable comonomers will vary according to `
the reacti~ity of these other comonomers. In most instances ; 10 such temperatures likewise are within the range from about 0 to 100C.
.. ~ . :
A large variety of comonomers can be used to form polymers with one or more acrylonitrile or substituted acrylo-nitrile monomers. For the most part, such monomers axe poly-merizable vinyl monomers. They include, or example: tl) esters o~ unsaturated alcohols, ~2) esters of unsaturated acids, ~3) ~inyl cyclic compounds, (4) unsaturated ethers, (~) unsaturated ketones, (6) unsaturated amides, (7) unsaturated aliphatic hydrocarbons, (8) vinyl halides, ~9) esters of unsaturated polyhdric alcohols ,. ~ ~.. ..
~e.g., butenediol), (10) unsaturated acids, (11) unsaturated ; acid anhydrides, ~12) unsaturated acid chlorides, and (13) unsatu-rated nitriles other than acrylonitrile.
', ? ~ ~
`~ Specific illustrations of such compounds are:
Esters c unsaturated alcchols, i~e., allyl, methallyl crotyl, l-chloroallyl, 2-chloroallyl, cinnamyl, vinyl, methyl-vinyl, l-phenallyl, butenyl, etc., and (a) saturated acids such.as for instance, acetic, propionic, buyric, valeric, caproic, stearic, etc.; (b) unsaturated acids such as acrylic alpha-sub-1 s~tituted acrylic (including alkacrylic, e.g., methacrylic, `1l 30 ethylacrylic, propylacrylic, etc.), crontonic, oleic, linoleic, i .. , . : .

;; -19-:, . ' `

., . ....... .:

7~Z
linolenic, etc., tc~ polybasic acids such as oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic, sebacic, etc., (d) unsaturated polybasic acids such as maleic, furmaric, '`
citraconic, mesaconic, itaconic, methylenemalonic, acetylene-dicarbonzylic aconitic, etc., te) aromatic acids, e.g., benzoic, phenylacetic, phthalic, terephthalic, benzolyphthalic, etc. `
2. The esters of saturated alcohols such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, 2-ethylhéxyl, cyclohexyl, benzyl, et~., with unsaturated aliphatic monobasic and polybasic acids, examples of which are illustxated ;~ . ...
above.
3. Esters o unsaturated polyhydric alcohols, e.g., `
,. . .
;butenediol, etc., with saturated and unsaturated aliphatic and aromatic, monobasic and polybasic acids, illustrative examples of which appear above.

4. Vinyl cyclic compounds including (a) monovinyl j;
51 aromatic hydrocarbons, e.g., styrene, o-, m-, p-chlorostyrenesr ~:,, -bromostyrenes, -fluorostyrenes, -methylstyrenes, -ethylstyrenes, ;, -cyanostyrenes, do-, tri- and tetra-, etc., -chlorostyrenes, ~
-bromostyrenes, -flurostyrenes, -methylstyrenes, -ethylstyrenes, ! ~'"
r~ cyanostyrenes, vinylcyclohexane, vinylfuran, vi~ylpyridine, ci~;`
vinyl~enzofuran,~divinybenzene, ~rivinylbenzene, allybenzene, N-vinylcarbazole,~N-vinylpyrrolidone, N-vinyloxazolidone, etc. ;~
; 5~. Unsaturated ethers such as, e.g., methyl vinyl ~;
;ether, ethyl vinyl ether, cyclohexyl vinyl ether; octyl vinyl ther, diallylether, allyl ethyl ether, etc. ~`
,'!` `: `' .
6. ~nsaturated ketones, e.g., me~hyl vinyl ketone, ethyl vinyl ketone, etc~ ;
7. Unsaturated amides, such as acrylamide, .
N-me~hylacrylamide, N-phenylacrylamide, N-allylacrylamide, ., .~
N-methylolacrylamide, N-allycaprolactam, etc~ ;
,! , ,` ' ~ ' .
; -20- `:~: ~;
' r ~ ~

: . 1,`.,:
~ ~7~
~ . . ,.. ..
;,.
.. , 8. Unsaturated aliphatic hydrocarbons, for instance, '' ' ;' ethylene, propylene, butenes, dienes, i.e., butadiene, isoprene, '~'~

; 2-chlorobutadiene, alpha-olefins, etc., typically having from up ' `

'~` to about 12 carbon atoms, moxe prefer'ably up to about 5 carbon ~ atoms.
:: .
';' 9. Vinyl halides, e.g., vinyl fluorice, vinyl chloride, ,' vinyl bromide, binyl iodine, vinylidene chloride, vinylidene '~

' bromide, allyl chloride, allyl bromide, etc.

10. Unsaturated acid anhydrides, e.g., maleic, ' 10 citraconic, propylacrylic, etc., examples of which appear above.

;' 11. Unsaturated acid anhydrides, e.g., maleic,', `

'l citraconic, itaconic, cis-4-cyclohexene-1, 2-dicarboxylic, bicyclo ' ~;

~', (2.2.1) 5 heptene-2, 3-dicarboxylic, etc.

'"' 1~. Unsaturated acid halides such as cinnamoyl, ';

;~;l acrylyl, methacrylyl, crontonyl, oleyl, ~umaryl, etc.

13. Unsaturated nitriles other than acrylonitrile, "

e.g., methacrylonitrile and other substituted acrylonitriles. '~

The acrylonitrile containing elastomers, many of ' '' ., . ., ~ .
i''~ which can be classified as rubber may be used with a siliceous filler. It may be readily vulcanized by conventional means.
As stated above the formation of the cellular structure ' ~' and the vulcanization andJor curing are adjusted in order to pre- ~;~
pare a cellular material having the compressibility and physical characteristics as set forth herein. For methods of preparing the cellular structure see the following references: H.J. Stern, . ,. i, . . .
~iljRubber: Natural and Synthetic, 2nd. Ed., Palmerton Publishing ~3 Co., N.Y., 1967, pp. 360-365; The Vanderbilt Rubber Handbook, ! `: j~ :
R.T. Vanderbilt Co., Inc., N.Y., 1958, pp. 463-4, 478-9, 486;

and W.J.S. Naunton, Ed., The Applied Science o~ Rubber, Edward ; 30 Arnold (Publishers) Ltd. London, 1961. While either an open cell ~ or closed structure is suitable, a predominantly closed cell ~ ' ;! ''-structure is preferred. `-:, ....................................................................... .
~ -21-... . .

~` 1~3~4~2 III. Epoxv Derived Elastomer The epoxy derived elastomers which can be used for form- ~ .
ing the compressible cellular material are those elastomers which comprise at least about 40 weight percent of polymerization units derived from an epoxy monomer or mixtures thereof, wherein the epoxy monomer has from about 2 to 12 carbon atoms, more preferably from about 2 to about 6 carbon atoms, and still more preferabl~
2 to 3 carbon atoms. The epoxy monomer or mixtures thereo is - more preferably present in the elastomers in a weight percent of at 10 least about 70 and still more preferably at least about 90. ;~
In a still more preferred embodiment of this invention, the epoxy elastomers are derived from epichlorohydrin preferably within s- , ' : . .
the weight percentage ranges as set forth above. In thi.s preerred iJ embodiment, the various comonomers set forth below can be ~ utilized with epiahlorohydrin. `~`
,.. . ....
The epoxy elastomers utilized in ~orming the com- i pressible cellular material are vulcanized and/or cured and ` the cellular structure formed using materials and process con- ;

jl ditions which are typical for epoxy elastomers. The materials .. ~ , .~ . .
I 20 and conditions utillzed are chosen in order to provide a com- ` ~-~: , . .. ..
-~ pressible cellular material which has performance characteristics j -~
as~set forth herein. ~
}t will be understood for the purposes of this , ~: -- .. .. ..
specification that the term epoxy elastomers i5 used in a ~eneric `~-sense to include homopolymers, copolymers, terpolymers and other ~ interpolymers which have molecular weights o~ at least about `~ 50,000, more preferably ~rom ahout 100,000 to about 3,000,000.
. ;

~ 30 ~
,.;., ,. ~ .
,~( ..~;, .

., . :: .
: ~ .
~- -22-"i I ~:
~:, . ,.i., :: .
:, , ,: ' '' . .:;;
,,.1 . . . .
,~' '.' ` `'~'' ;' .. . . . . . . . . . ~ . ... . .. ... . ,.. . ... . ....... ..... ...... .. ~ . . . . ... ::.

. ~

~ 37~L4Z
. .
. ....
. The various copolymerizable monomers as set forth below can ~-vary widely but should not materially deteriorate the epoxy cellular material in hydrocarbon resistance, abrasion resis-tance and performance characteristics set forth herein.
- A large variety of monomers can be used to form ; epoxy derived polymers. For the most part, such monomers are j~;
"4' polymerizable including an epoxide linkage or linkage which !i can react with an epoxide linkage. Generally an epoxide with up to about 12 carbon atoms is acceptable, more preferably an `
10 epoxide with up to about 6 carbon atoms and most preferably an ~
,, ~ ~ ,.
epoxide with up to about 3 carbon atoms. Moreover, it is preferred to utilize an epoxide which is substituted with polar groups, 'l such as halogens, oxygen, eta. They include, for example~

~, (1) ethylene oxide, (2) propylene oxide, (3) butylene oxide, ;

~4) 2,3-epoxy-1-propanol, (5) 2,3-epoxy-2-methylbutane, (6) ~' epichlorohydrin, etc.

~;j A preferred material for use as the cellular plastic ~ are rubbers derived from epichlorohydrin.
;,: . ..... ..
These rubbers have high chlorine content and are 20 similar to neoprene in oil resistance and non-inflammability. -~

: .'' ~ , They have the additional advantage of good low temperature flex- ?',~ '~' . .

````i ibility.

~i Two types of these polymers referred to as CHR being derived from epichlorohydrin/ and as CHC from epichlorohydrin ~

~i are ethylene oxide. ~:?',,':` .,:
,, i.` ~
One means of preparation is with a alass of catalysts h;

~¦ which are reaction products of aluminum alkyls and water, see `

~ U.S.Patent 3,135,705. Any suitable polymeri~ation of epoxy `~¦ linkage is acceptable. ~`~

;~ 30 The formation of the two types of rubber may be ¦ formulated as follows:

23- ;
~,."~ ,,,;
~ B ;
;., .
V~

': `

374~2 : catalyst .~ CHR EpichlGrohydri.n ~CHR :~
~: CH2 _ ~H---CH2Cl~(CH2 - CH - O -~n ~ ~" CH2Cl r ^~ n = ca.5000. jj ;
~ catalyst ~.:
CHC Epichlorohydrin ~ Æthylene oxide . ~C~C
~ - CH2Cl+C ~ 2 - ~(CH2-clH-O CH~-CH2-O-)n ; 10 n = ca.200000.
~l CHR has a chlorine content of about 38.4% and a specific gravit~ ~
, , , . . - .i~' : , .: ' ' of about 1.36. The chlorine content of CHC is about 26.0% and ~., the specific gravlty about 1.27. `~
. The processing properties are excellent. Curing i9 ``. .
brought about by reagents which will react with the CH3Cl group, ;;.
., for example, 2-mercaptoimidazoline. Typical compounding is as ,: , ,,:. . .
follows: .`
~: T~ST MIX FOR CHR AND CHC
: ~Polymer ~ ~ 100 100 Zinc stearate~ ~ 1.0 1.0 EF-carbon~black ~ ~ 50 ~50 Red~lead;
Ni; di~utyl~dithiocarbamate ~ loO 1~0 '~
2-Mercaptoimidazoline :: .
(NA-22)~
Press-cured 4S minutes at . ;;
: 155C t310P) 1.5 1.5 ~: CHR CHC '.:
: Unaged Aged* Unaged Aged~ : ;
, I .... ...
Tensile strength, p.s.i. : 2125 2250 2170 1645 Elongation at break, ~ . 260 150 240 200 `
., .
200% Modulus 1800 - 1985 ~`i Hardness, Shore 76 83 75 68 .:~ . , , .:, , .,; ~j ~ ,.
... . ...

Jr ~ r~ .
,., ,. ', .

- ~3 7~4 *6 days at 150C (300F) in a circulating air oven.
+5 days at 150C (300F) in a circulating air oven. :`
, . .. .
l of course, additives or other compounds can be added to ~ . .. .
these rubbers (cellular plastic) in amoun~s which will not hinder the desired attributes of the cellular plastic (e.g., good resistance, flexibility, etc.).
As stated above, the formation of the cellular structure ~ -;
; and the compounding vulcanization and/or curing are adjusted in !,'~";' ' order to prepare a cellular material having the compressibility and physical characteristics as set forth herein. For methods of preparing the cellular structure see the following references:
H.J. Stern, Rubbex: Natural and Synthetic, 2nd. Ed., Palmerton Publishing Co., N.Y., 1967, pp. 360-365; The Vanderbilt Rubber `
Handbook, R.~. Vanderbilt Co., Inc., N.Y., 1958, pp. 463-4, 478-9, 486; and W.J.S. Naunton, Ed., The Applied Scienae of Rubber, ~ ,, l , .. .
; Edward Arnold (Publishers) Ltd. London, 1961. While either `~
an open cell or closed cell structure is suitable, a predominantly ! I I ` . .
l closed cell structure is preferred. ,; ~
; ~ :

~c;
.: ~ ",i,~, , .~., ','~ ~ , ..
,-, " ,. ~.. .
~.' ~
i' .. 3 ~
~i~

~ ;
~,~"~ ', ' ., .
~. 1 ....
, ~ ~

,, IV. Fluorin~ ~ont~lning Elastomers ', ~; The fluorine containing elastomers which can be used ' ,i-' for forming the compressible cellular material are those elastomers ~','-. ,; .
' which comprise at least about 10 weight percent of fluorine. r' ' ".' i The fluorine is more preferably present in the elastomers in a weight '~ ~
.. ~ " .
, percent of at least about 35 and still more preferably at least about '' '~
... . ... .. .
' 60. In a still more preferred embodiment of this invention, the ' fluorine containing elastomers are derived from vinylidene fluoride ,` '' preerably within ~he weight percentage rang~s as set ~orth above. ''~

~'f 10 The fluorine containing elastomers utilized in forming '~-,', ,' the compressible cellular material are vulcanized and/or cured ~ '' , and the cellular structure formed using materials and process ,' conditions which are typical for 1uorine containing elastomers. '"

;, The materials and conditions utilized are chosen in order to , ' pxovide a compressible cellular material which has per~ormanc~ ,~

'; characteristics as set forth herein.

'"', It will be understood or the purposes of this ,, ' ;1 f' ";
,, specification that the term fluorine containing elastomers is used '`' , in a generic sense to include homopolymers, copolymers, terpolymers ''; ', ~, 20 and other interpolymers which have molecular weights of at least ,' ,,", about 50,000, more preferably from about 100,000 to about 3,000,000. ;,~i, The Yarious copolymerizable monomers as set forth below can '~' ' vary widely but should~not materially deteriorate the fluorine '~' containing cellular~material in hydrocarbon resistance,''abrasion resistance and performance characteristics as set forth herein.
' ' The fluorine containing monomer is usually polymerized ,,',,, ~ by ~ree radical polymerization technique ~also known as the addition '`

.,,` , ~;:
~, .. .
~ 30 .,,: ,' ' ... ,: , . . :
:

i . . ~

''; ,' ' `'':. ,' .: ,. .:
? ' .

.~ ~

r~ ~
- 1~3744Z
polymerization technique) although other techniques may be used.
Such technique consists of contacting the monomer~s) with poly-merization initiator either in the absence or presence of a diluent at a temperature usually between 0 and 200C. The polymerization initiator i5 a substance capable of liberating a free radical under the conditions of polymerization, e.g., benzoyl peroxide, tert-butyl hydroperoxide, cumyl peroxide, postassium persulfate, acetyl peroxide, hydrogen peroxide, axobisisobutyronitrile, or perbenzoic acid. Ammonium persulfate is commonly used.
The fluorine containing monomer may also be polymer-ized or copolymerized using an anionic initiator such as naphtyl-sodium or butyllithium in tetrahydrouran solution ox sodium metal in liquid ammonia solution. `, The polymerization o~ the ~luroine containing monom~r may also be efected by other polymerization techniques such as by the use of Ziegler type catalysts, gamma ray irradiation, or thermal techniques.
The diluent for the polymerization mixture may be either an inert solvent such as benzene, toluene, xylenP, cyclo-hexane, hexane, naphtha, tetrahydrofuran, white oil, or doaecane;
or a non-solvent such as water or liquid ammonia. Thus, the polymerization can ~e carried out in bulk, solutian, emulsion, . ,~
i~or suspension. ~ ;
~The temperature for the polymerization depends on the ~ ! ' .
catalyst system employed and to some ex~ent upon ~he nature oX
the monomers to be polymerized. Thus, the copol~merization o~ an ; fluorine containing monomer with a very reactive compound may be catalyzed a~ temperatures from about -100 to 50C., preferably ~ 30 at ~70 to 0C. On the other hand, the optimum temperature ~or .'` ' . . ;

.- ' 37~4;~

effecting the free radical catalyzed homopolymerization of a~
~luorine containing monomer is usually from 0 to 150C., `~
preferably 80 to 125C. Similarly, the optimum temperatures for effecting the free radical catalyzed interpolymeri~ation of for example vinylidene fluoride with one or more polymer-izable comonomers will vary according to the reactivity of these other comonomers In most instances such temperatures likewise are within the range from about 0 to 150C. ;`
A large variety of comonomers can be used to form ,~.
polymers with one or more fluorine containing monomers. For the ` most part, such monomers are polymerizable vinyl monomers and ~`
; there partially or completely fluoronated counterpaxts (i.e., substituting fluorine for hydrogen). They include, for example:
~1) esters of unsaturated alcohols, (2) esters of unsaturated acids, ~3) vinyl cyclic compounds, (4) unsaturated ethers, (5) unsaturated ketones, (6) unsaturated amides, (7~ unsa~urated ~ ;
aliphatic hydrocarbons, ~8) vinyl halides, ~9) esters of unsat-i;'7 urated polyhdric~alcohols ~e.g., butenediol), ~10) unsaturated acids, (11) unsaturated acid anhydrides, tl2) unsaturated acid i . , chlorides, and~(13) unsaturated nitriles.
Specific illustrations of such compounds are:
sters of unsaturated alcohols, i.e., allyl, ~.~; ;. .
~ methalIyl crotyl, l-chloroallyl, 2-chloroallyl, cinnamyl, vinyl, ;; methyl-vinyl, l-phenallyl, butenyl, etc., and (a) saturated acids such as for instance, acetic, propi~nic, buyric, valeric, caproic, il~ stearic, etc.; ~b) unsaturated acids such as acrylic alpha-sub-siti~uted acrylic (including alkacrylic, e.g., methacrylic, ethylacrylic, ~ropylacrylic, etc.), crontonic, oleic, linoleic, "
linolenic, etc~, (c) polybasic acids such as oxalic, malonic, ~ ;
succinic, glutaric, adipic, pimelic, suberic, axelaic, sebcic, ';'`'' ' :

:, - ....
~ -28- ~

1~374gLZ ~:
; ~ _ .. .
~ ~' ! ~ .. ..
- ~ ~c., (d) unsaturated polybasic acids such as maleic, furmaric, oitraconic, mesaconic, itaconic, methylenemalonic, acetylene- -~
- dicarbonzylic aconitic, etc~, ~e) aromatic acids, e.g., benzoic, phenylacetic, phthalic, terephthalic, benzolyphthalic, etc~ -; 2. The esters o~ saturated alcohols such as methyl, - ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, 2-ethylhexyl, cyclohex~l, benzyl, etc., with unsaturated aliphatic monobasic and polybasic acids, examples of which are illustrated above.
3. Esters of unsaturated polyhydric alcohols, e.g., butenediol, etc., with saturated and unsaturated aliphatic and aromatic, monobasic and polybasic acids, illustrative .. , .-examples of which appear above.
4. Vinyl cyclic compounds including ~a) monovinyl ``
aromatic hydrocarbons, e.s., styrene, o~ , p~chlorostyrenes, -bromostyrenes, -~luorostyrenes, -methylstyrenes, ~ethylstyrenes, -cyanostyrenes, do-, tri- and tetra-, etc., ; -chlorostyrenes, -bromostyrenes, -flurostyrenes, -methylstyrenes, ethylstyrenes, -cyanostyrenes, vinylcyclohexane, vinylfuran, vinylpyridlne, vinylbenzofuran, divinybenzene, trivinylbenzene, allybenzene, N-vinylcarbazole, N-vinylpyrrolidone, N-vi~yloxa-zolidone, etc. ;
: 5.: Unsaturated ethers such as, e,g.f methyl vinyi ether, ethyl vinyl ether, cyclohexyl vinyl ether; octyl vin~l ether, diallylether, allyl ethyl ether, etc.
6. Unsaturated ketones, e.g., methyl vinyl ketone, ethyl vinyl ketone, etc.
7~ Unsaturated amides, such as acrylamide, ~`
~-methylacrylamide, N-phen~lacrylamide, N-allylacrylamide, N-methylolacrylamide, N-allycaprolactam, etc.

., I .
... -;
. ,~ . .
','.................................... ; .

337~42 ~.
- ..,... :-... .. .
8. Unsaturated aliphatic hydrocarbons, for instance, -ethylene, propylene, butenes~ butadiene, isoprene, 2-chlorobutad-iene, alpha-olefins, etc. ;
9. Vinyl halides, e.g., ~inyl fluorice, vinyl chloride, ~inyl bromide, binyl iodine, vinylidene chloride, vinylidene brom-;~ .. .
ide, allyl chloride, allyl bromide, etc.
10. Unsaturated acid anhydrides, e.g., maleic, citra~
conic, propylacrylic, etc., examples of which appear above.
, 11. Unsaturated acid anhydrides, e.g., maleic, 10 citraconic, itaconic, cis-~-cyclohexene-l, 2-dicarbonxylic, , ; bicyclo ~2.2.1) 5-heptene-2, 3-dicarboxylic, etc.
;,;:
;~ 12. Unsaturated acid halides such a~ cinnamoyl, I
.:, ; ., acrylyl, methacrylyl, crontonyl, oleyl, fumaryl, etc.
13. Unsaturated nitriles, e.g., aar~lonitrile, `
methacrylonitirle and other substituted acrylonitriles.
Some particular types of this elastomer arè copolymers "
~ of vinylidene fluoride with chlorotrifuloroethylene, and/or i~l hexafluoropropylene, and a tripolymer of vinylidine fluoride, ¦ hexa1uoropropylene, and tetrafluoroethylene. Other suitable 20 types are an elastomeric copolymer of vinylidine fluoride and hydropentafluoropropylen and a tripolymer o~ these monomers and tetrafluoroethyl~ene.
Elastomers are based on vinylidene fluoride have been prepared in most cases by radical polymerization in emulsion by the use of organie or inorganlc peroxy compounds, such as ammonium persulfate, as an initiator. A fluourinated carboxylic acid soap may be used but is no~ required. Usaful temperature ~, "
.and pressure ranges are 80C to 125C and 300 to 1500 psig, respectively. Molecular weight is controlled by the monomer/
initiator ratio or by the use o certain chain transfer agents :. ! ',, : ' , ,'`~ '' ',' ' ' '"'.

-30- ~
' `. .'' such as carbon tetrachloride, chloroform, alkyl mercaptans, alkyl esters, and iodine, bromine, chlorine, or selected halogen sal~s.
Iow molecular weight fluid or semifluid polymers suita~le for use as caulk bases and processing aids for fluoro~
carbon rubbers can be used. Polymerization o~ vinylidene fluoride and hexafluoropropylene in the presence of certain chain transfer agents such as aliphatic alcohols, ketones, and esters produces ~iscous oils and semi-solids which can be cured with diamines.
Another approach produces useable polymerica dicarboxylic acids by dehydrofluorinating a hi~h molecular weight vinylidene fluoride/
;.
hexa~luoropropylene copolymer or vinylidene fluoride/hexa~luoro-propylene/tetra~luoroethylene tripolymer with an amine ox other base, and oxidizing the resulting unsaturated polymer with poTa$~;u~
permanganate in acetone or glacial acetic acid or with fuming ~;
~; nitric acid. Carboxyl or carbalkoxyl terminated vinylidene fluoride/hexa~luoroprop~lene dipolymers have al50 been made by the use of special initiators and are suitable. For example:

~ ~ ~
~I ROCR Cl ~RO RLC OCRf OR
aqueous 2RO f + 2Co2 + NaCl 2RO R~ + 2XcH2acF2 + ~ CF2=C~?-CF3 . ~ . . AO~i~Rf~l (CE'2--CEI;~) x--~CF2~F) y~ n--(RE) ~OR
~ ::{ : .~ These polymers can be cured ~ri~h metal oxides, epoxides, or ~, . .
;~ 30 azirane dexivati~es.

, 1 - , , l -31-.'`,1, ' .',"` . ' '~ '' .

Z
Another type of fluorine containing elastomers suitable are fluorosilicone elastomers. ~luoralkylsiloxanes or other ~ ;
suitable high molecular weight polymers from which solvent resis-tant elastomers having good low and high temperature flexibility -~
.
can be used.
The fluorosilicone elastomers can be made by ionic polymerization processes. One preparation of basic monomer and ., .; . .
elastomer is shown below:
HF
.. 10 CC13CH=CH2 - > c~3cH-cH2 .
~, . . . . .
init.
CF3CH=CH2~CH3SiHC12 ~CF3CE2CH2SicH3cl2 ;

;, CF3CH2CH2SiCH3Cl2 ~Iydrolyzate (linear and ~, cyclic species) ~ HCl~ ;
' base Hydrolyzate- 3(RR'SiO)3tdistill)~, , ~ where R = CH3 - , and R' = CF3CH2CH2 -The cyclic trimer is purified by distillation and then converted to polymer at elevated temperature in the presence of a basic `~
catalyst. The polymer is in equilibrium with cyclic trimer and ~, cyclic tetramer and~the system greatly favors the cyclic tetramer. -~
Hence, the polymerization must be stopped before equilibrium i5 "
reached and careful control of reaction temperature and time 1` -~- is essential. In commercial practice, gum polymers of a de~ree of poIymerization o~ about 6000 are obtained. A small number of i~
, vinyl substituents can be introduced into the polymer by means ;`~ a comonomer in order to facilitate peroxidic curing.
:; ,: . .:
;'`~ 30 The amount of fluorine which can be introduced into a ~.,.:: : . .
~ ` ~luorosilicone rubber is limited somewhat by the tendency of ...
"
. .,.,I , ~ .,: .:

;:, "'~ ~ , " ' ' .~;, .. .
:, `j '; ' 3~ -~- or ~-fluoralkyl substituents on silicone to undergo hydrolytic or thermal cleavage.

nCF3Si_ > (CF2)n = nFSi-Q
3CH2si= ~ CF2=CH2 = FSi-Thus, the preference for the ~-fluorinated substituent. Despite this limitation, polymers with very good resistance to aliphatic and aromatic hydrocarbon fluids are obtained. The solubility parameter for a methyl, 3,3,3,-trifluoropropylsilicone polymer is 9.6 similar to the value for a typical fluorocarbon elastomer and substantially different from that of a dimethylsilicone polymer, which is about 7.5. Methyl, 3,3,3-trifluoropropylsilicone `~
rubher is amorphous, has a density of 1.25 g. cm~3 at 25C, and a glass transition temperature of -65C.
Both one-part and two-part room-temperature-vulcanizin0 fluorosilicone elastomers can also be used.
Other suitable 1uoronated elastomers are perfluoro (alkyl vinyl ether) copolymers, ;! tetrafluoroethylene/perfluoronitrosomethane elastomers, `
`l and ~`
;l 20 perfluoroalkylene triazine elastomers.
;
~,, .
As stated above the formation of the cellular structure and the vulcaniz~ation and/or curing are adjusted in order to prepare a cellular material having the compressibility and physical ~;
characteristics as set forth herein. For methods of preparing the ~l~ cellular structure see the following references: H.J. Stern, -Rubber: Natural and Synthetic, 2nd. Ed., Palmerton Publishing Co., N.Y., 1967, pp. 360-365; The Vanderbilt Rubber Handbook, R.T. Vanderbilt CQ., Inc., N.Y., 1958, pp. 463-4, 478-9, 486;
and W.J.S.Naunton, Ed., The Applied Science of Rubber Edward :; 30 Arnold (Publishers) Ltd. London, 1961. While either an open c cell or closed cell structure is suitable, a predominantly closed ~ ~, ~, cell structure is preferred.
~
: ,.~
,, ~ ~33~
~

. " .:: .
.: ' " ' ~ql37442 ~ :
The exposed face of the compressible cellular plastic , .
material can be coated with the same plastic material used to .: ,;- ~ . ., form the cellular plastic material. Thus, the face can have a surface skin or coating which contacts the receiver inlet to which liquid is being dispensed. In addition, the face of the compxessible cellular plastic material can have a surface skin or coating which is of a different material such as a synthetic r~sinous matexial or a natural occurring material, both of which !~
are substantially resistant to fuel liquid and vapor being .;, .... ..
10 dispensed. The coating material, either the same or different ~;
from the compressible cellular plastic material, has to be resilient, that is, the material de~orms to a certain extent when the spout o~ the nozzle is inserted into the fuel pipe. Typical examples of resilient material are leather and synthetic resin such as polychloroprene (neoprene~. It is contemplated within the scope of this invention that the term "compressible cellular ~' plastic material" includes such a aoating or different resilient fi; material affixed thereto to form the exposed face seal.
;i m e thlckness of the compressible cellular plastic ;~
20 material is not critical, and may vary from a minimum thickness J~ ~-required to provide~the mLnimum seal to a maximum ~hickness which would be dictated by economic considerations (i.e., an ` ~ extremely thick material~would not be required). Typically, the c compressible cellular plastic material is utilized in a thickness ~ ;~
z`~ which may range ~rom about 1/16 inch to about 1/2 inch. ~;
The invention can be better appreciated by the ~ following non-limiting examples: ~
; ~ ' '.

. . .

.. . .....
, -3~-,,., .'.. " ~.
. ~ , ''':, ;`; ~'' 7~4;2 EXAMPLE III
An OPW #7 vapor recovery gasoline dispensing nozzle is equipped with a polychloroprene bellows boot, one end of which is attached to the noæzle housing, the other end surrounding the nozzle outlet having only an exposed plain surface. The bellows boot is substantially of the same geometrical configuration as the boot set forth in Figure I. The nozzle has equipped a `,1'4 face comprising a closed cell polyacrylate foam of approximately :k 1/4 inch thickness. The sealing wear and abrasion resistance ~ -utilizing the nozzle with the foam face provides for an improved ., ;.
nozzle.
EXAMPLE IV
' A modified OPW ~7 vapor recovery nozzle i9 equipped , , !
with a polychloroprene bellows boot one end of which is a~tached ~ to the nozzle housing/ the other end surrounding the nozzle outlet ; having a surface face. The nozzle is made to include a 3/4 inch ,,. j ,~, vapor return line on the bottom of the handle area. A square `-~
cross-section retention latch is used on the spout. The bellows boot is substantially the same geometrical configuration as the boot set forth in Figure I. The surface of a first boot is ' ~, modified by affixing a unidirectional magnet to the boot surface.
The magnet is further modified by the bonding of a polyacrylate , elastomer foam having a thickness of 1/8 inch to the unidirectional ,.,. ,; ~
magnet.

EXAMPLE V

When in Example III, the nozzle is equipped with a face ;~; comprising closed cell acrylonitrile foam, closed cell epoxy ¦ foam, or closed cell fluorine containing foam, similar results are . ,j ...
obtained in that the sealing wear and abrasion resistance utilizing the noæzle with the foam face provides for an improved ``

nozzle.

Again hydrocarbon recovery is improved with the nozzle ! having the elastomer foam of this invention.

i 35 :.~ s; ::, :.,

Claims (39)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a liquid-dispensing nozzle assembly for delivery of liquid from a liquid source to a liquid receiver having an inlet and provided with means to prevent escape of vapor during delivery of liquid to said receiver inlet from said source, said nozzle assembly comprising:
(1) a liquid-dispensing nozzle having a nozzle inlet, a nozzle housing and an elongated discharge spout adapted for insertion into said receiver inlet;
(2) a flexible vapor collector surrouding, in spaced relation thereto and forming a chamber therearound, the upper portion of said spout nearest said nozzle housing, said chamber being in fluid communication with the receiver inlet, when said spout is inserted into said liquid receiver inlet, one end of said vapor collector being sealed to said nozzle housing, or in proximity thereto, a sealant means carried by the other end of said vapor collector for forming a surface seal against the outer surface of said receiver inlet, said spout extending beyond the other end of said vapor collector; and (3) means for removing vapor from said chamber; and, said sealant means of said vapor collector having affixed thereto a compressible cellular plastic material which forms an exposed face seal, said face seal being adapted to contact said receiver inlet when said discharge spout is inserted therein for sealing said receiver inlet against vapor loss during delivery of liquid to said receiver inlet through said spout.

2. A liquid dispensing nozzle assembly of claim 1 wherein said compressible cellular plastic material is obtained from a polymer selected from the group consisting of polychloro-prene latex, polyethylene, silicone, urethane polymer, poly(vinyl chloride), polytetrafluoroethylene, cellulose acetopropianate, and a urea-formaldehyde resin.

3. A liquid dispensing nozzle assembly of claim 1 wherein the compressible cellular plastic material is obtained from a polymer selected from the group consisting of polychloroprene latex, urethane polymer, and polytetrafluoro-ethylene.

4. A liquid dispensing nozzle assembly of claim 3 wherein the compressible cellular plastic material is obtained from urethane polymer.

5. A liquid dispensing nozzle assembly of claim 1 wherein said flexible vapor collector comprises a flexible bellows.

6. A liquid dispensing nozzle assembly of claim 3 wherein said flexible vapor collector comprises a flexible bellows.

7. A liquid dispensing nozzle assembly of claim 4 wherein said flexible vapor collector comprises a flexible bellows.

8. A liquid dispensing nozzle assembly of claim 1 wherein the surface of the exposed face seal comprises a material different from the compressible cellular plastic material.

9. A liquid dispensing nozzle assembly of claim 8 wherein said different material is leather.

10. A liquid dispensing nozzle assembly of claim 1 wherein said liquid is gasoline and a square cross-section retention spring is provided around a major portion of said discharge spout.

11. A liquid dispensing nozzle assembly of claim 9 wherein said liquid is gasoline and a square cross-section retention spring is provided around a major portion of said discharge spout.

CLAIMS SUPPORTED BY SUPPLEMENTARY DISCLOSURE

12. A liquid dispensing nozzle assembly of claim 1 wherein said compressible cellular plastic material is obtained from an elastomer selected from the group consisting of:
(1) a polyacrylate elastomer;
(2) an acrylonitrile containing elastomer;
(3) an epoxy derived elastomer; and (4) a fluorine containing elastomer.

13. A liquid dispensing nozzle assembly of claim 12 wherein said compressible cellular plastic material is obtained from a polyacrylate elastomer.

14. A liquid dispensing nozzle assembly of claim 13 wherein the compressible cellular plastic material is obtained from a polymer selected from the group consisting of polyacrylate elastomers wherein at least 50 weight percent of the polymerization units are derived from an alkyl acrylate or mixtures thereof wherein the alkyl portion has from about 1 to 6 carbon atoms.

15. A liquid dispensing nozzle assembly of claim 14 wherein at least 70 weight percent of the polymerization units are derived from an alkyl acrylate or mixtures thereof wherein the alkyl portion has from about 1 to 6 carbon atoms.

16. A liquid dispensing nozzle assembly of Claim 14 wherein at least 90 weight percent of the polymerization units are derived from an alkyl acrylate or mixtures thereof wherein the alkyl portion has from about 1 to 6 carbon atoms.

17. A liquid dispensing nozzle assembly of claim 13, 14 or 15 wherein said polyacrylate elastomer is derived from ethylacrylate.

18. A liquid dispensing nozzle assembly of claim 12 wherein said compressible cellular plastic material is obtained from an acrylonitrile containing elastomer.

19. A liquid dispensing nozzle assembly of claim 18 wherein the compressible cellular plastic material is obtained from a polymer selected from the group consisting of acrylonitrile containing elastomers wherein at least 5 weight percent of the polymerization units are derived from acrylonitrile.

20. A liquid dispensing nozzle assembly of claim 19 wherein from about 18 to about 40 weight percent of the polymerization units are derived from acrylonitrile.

21. A liquid dispensing nozzle assembly of claim 19 wherein from about 25 to about 30 weight percent of the polymerization units are derived from acrylonitrile.

22. A liquid dispensing nozzle assembly of claim 18 wherein said acrylonitrile elastomer is polymerized with an olefin.

23. A liquid dispensing nozzle assembly as in claim 22 wherein said olefin is a 1,3-diolefin.

24. A liquid dispensing nozzle assembly of claim 23 wherein said 1,3-diolefin is 1,3-butadiene.

25. A liquid dispensing nozzle assembly of claim 12 wherein said compressible cellular plastic material is obtained from an epoxy elastomer.

26. A liquid dispensing nozzle assembly of claim 25 wherein the compressible cellular plastic material is obtained from a polymer selected from the group consisting of epoxy elastomers wherein at least 40 weight percent of the polymerization units are derived from an epoxy monomer or mixtures thereof which have from about 2 to 12 carbon atoms.

27. A liquid dispensing nozzle assembly of claim 26 wherein at least 70 weight percent of the polymerization units are derived from an epoxy monomer or mixtures thereof which have from about 2 to 6 carbon atoms.

28. A liquid dispensing nozzle assembly of claim 26 wherein at least 90 weight percent of the polymerization units are derived from an epoxy monomer or mixtures thereof which have from about 2 to 3 carbon atoms.

29. A liquid dispensing nozzle assembly of claim 25, 26 or 27 wherein said epoxy elastomer is derived from epichlorohydrin.

30. A liquid dispensing nozzle assembly of claim 12 wherein said compressible cellular plastic material is obtained from a fluorine containing elastomer.

31. A liquid dispensing nozzle assembly of claim 30 wherein the compressible cellular plastic material is obtained from a polymer selected from the group consisting of fluorine containing elastomers which have at least 10 weight percent of fluorine.

32. A liquid dispensing nozzle assembly of claim 31 wherein at least 35 weight percent of the elastomer is from fluorine.

33. A liquid dispensing nozzle assembly of claim 31 wherein at least 60 weight percent of the elastomer is from fluorine.

34. A liquid dispensing nozzle assembly of claim 30, 31 or 32 wherein said fluorine containing elastomer is derived from vinylidene fluoride.

35. A liquid dispensing nozzle assembly of claim 12 wherein said flexible vapor collector comprises a flexible bellows.

36. A liquid dispensing nozzle assembly of claim 12 wherein the surface of the exposed face seal comprises a material different from the compressible cellular plastic material.

37. A liquid dispensing nozzle assembly of claim 36 wherein said different material is leather.

38. A liquid dispensing nozzle assembly of claim 12 wherein said liquid is gasoline and an essentially square cross-section retention spring is provided around a major portion of said discharge spout.

39. A liquid dispensing nozzle assembly of claim 37 wherein said liquid is gasoline and an essentially square cross-section retention spring is provided around a major portion of said discharge spout.