CA2031100A1 - Thermoplastic copolyetherimide ester elastomer-acrylate rubber compositions - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Thermoplastic elastomer compositions are disclosed which comprise a thermoplastic copolyetherimide ester blended with a crosslinkable alkylacrylate rubber component. The rubber is subject to crosslinking during melt mixing resulting in a thermoplastic processable material.

Description

~ CP-17~0) THERMOPLASTIC ~POLYET~ERIMIDE ESTER 2 0 ~110 ELASTOMER-~CRY~ATE RUBBER COMPOSIT~OMS
The presene inven~ion relates to blends o~
copolyeehesimide escer ~nd a rubbery crosslinkable alkylacr~ate elastomee.
BACRGROUND OF T~E INVENTION
~ her~oplas~ic elastomers o~ the type known as polyetherimide esters provide a variety of unique and excellent properties and are pacticularly useful in e~tru~ion and molding applications.
Polyetherimide esters prepared ~rom diols, dicarboxylic acids and polyoxyalkylene diimide diacids are ther~oplastic elastomers having an excellent combination o stress-strain properties, low tensile set, hlgh melting temperatures and excellent strength, toughne~s and flexibility properties. All of these propertleq are vario~sly useful in many elastomer appllcat~on~. Polyet~erimides also proce3s well, due to their rapid crystallizaeion rate and excellent moldabillty characteristics. Elastomers with the low flexural modulu~ o~ polyetherimide esters in combinaeion with any of the a~ocementioned advantaqeous propecties have gained wide accep~ance in the field of elastomecs.
Nonetheless, it ha~ now been found that polyetherimide e~ters can be improved or enhanced for cert~in app1ications, especially with respect to impeoving the qsoftness~ (lower durometer) of the elasto~er, while retaining satisfactory tensile propectie~. The improvements are accomplished by blendinq a rubbery crosslinkable alkylacrylate elastomer with the polyetherimide ester and crosslinking.
Work ha~ been patPnted in which a rubber is mixed with a theemoplastic re~in and subsequently crosslinked while the ingredients are being mixed.
Ge~ler et al., United States Patent No. 3,037,954 : , . ::, . :,, ~ : :

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

~ CP-12040) 2~3111)~
demonstra~ed ~ynamlc curLng" o~ a ~ut~l ~ubber/pol~-propylene blend. ~lscher, United Sta~es Paten~ ~lo.

3,758,643, partiall/ cured EPDM rubber in the pre3ence of a polyolefin. ~ther polyolefin/rubber vulcanizates S in which the ~ubber is pol~butadiene, natural rubber, isoprene and EPDM are disclosed in United States Pa~ent Nos. ~,104,210 4,130,535: and 4,311,628. In United State~ Patent No. ~,594,390, a continuous pcocess for preparing EPDM/polypropylene dynamic vulcanizates is reported. The Monsanto Company commercially produce~
an EPDM/polypropylene dynamic vulcanizate under the ~rade name nSANTOPRENE~, and a nitrile rubber/polyolefin dynamic vulcaniza~e under the trade name "GEOLAST~.
Further, Uni~ed States Patent No. 4,801,647 discloses an EPDM~cry~tallLne polyolefin dynamic vulcanizate.
Dynamic vulcanization ha~ also been disclosed employing copolyesters. European patent, EP 0 293 821 A2, d~sclo~e~ a multiblock cop~lyester melt mixed with polychloroprene rubber which is then crosslinked during mixing. In United States Patent No. 4,739~012, a seq~ented thermoplastic copolyester is bleneded with a ~cond co~position which is a blend of two partially ~
crosslinked polymers, such as PVC oc PVDC and a ~ -copolymer of ethylene and one or more ethylenically unsatura~ed comonomers prepared by dynamic vulcanization.
Acrylic rubbers are also known to be employed in thermopla tic dynamic vulcanizate Coran et al., Rubb~ Che~. and Tech., 55, 116 (1982), disclose a matrix of polymers and rubbers used in the preparation 30 of dynamic vulcanizate compositions in which polyacry1ate -~
rubber was used however, not with copolyetherimide e~ter~. Wolfe, United States Patent No. 4,782,110 disclo~e~ dynamically vulcanizinq ethylene-alkylacrylate copolymer rubbers with crystalline polyolefins.

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': . , ' ~ ' - -3- ! ~CP-12040 ) 203l~no Coran e~ al., United States Patent ~o.

4,327,199, ~isclose employing an ethylene-acrylic type copolymer cubber containing free carboxylic moieties in blend~ with polyesters such as P8T. A metal oxide ls S used as a source Oe metal ions to neutralize the pendant acid groups, ~orming an ionomeric network structure as distinguished from covalent bond formation. In Coran et al., United states Patent Nos. 4,310,638 and 4,473,683 the ethylene acrylic copolymer is blended with a nylon ~esin and a meeal oxide and amorphous styrene based re in~ and a metal oxide, respectively.
Also to be mentioned are United States Patent -Nos. 4,116,914 ~eehylene vinyl acetate rubber dynamically vulcanized with polyolefins~; 4,480,074 (two step proceqs ~or dynamically vulcanizing an EPDM/PP
vulcanizate with additional EPDM~; 4,226,953 (nitrile rubber dyna~ically ~ulcanized with s~yrene-acrylonitrile re~inq); 4,20~,407 (chlorinated polyethylene dynamically vulcanized with nylon resins~; 4,287,324 (epichlorohydrin rubber dyna~ically vulcanized with polye~ters such as P~T); and 4,593,062 (mixture of halogenated butyl rubber and polychloroprene dynamically vulcanized with polyole~ins such as PP and PE). Special mention is made of EPO 327 010 A2, which discloses blends of polyether ester copolymers with polyacrylate elastomers.
None of these however disclose a polyacrylate rubber which ha~ been dynamically vulcanized with a thermopla3tlc copolyetherimide es~er. It has now been dlscovered that dynamically vulcanizing a polyacrylate rubber with a thecmoplastic copolyetherimide ester unexpectedly pcovides an elastomer composition with improved softness while retaining excellent tensile pcopertie~.

.' : ':

' ~

~ 4- (~CP-12040) 2 0 ~
SUMMARY OF T~E INV':NTION
According to the pce~ent invention, there i5 provided a ~hermoplastic elastomer composition comprising:
(A) a polyetherimide ester copol~mer;
(~) a rubbery alkylacrylate, and (C) a crosslinking agent.
Th~ preferred polyetherimide e~ter copolymer comprise~ the reaction product of ( a) one or more low molecular weight diols: (b) one or more dicacboxylic acids; and (c~ one or more polyoxyalkylene diimide diacidq. Mo t preferably the diol component (a) comprlse ~ro~ about 60 to abou~ 100 mole percent 1,4-~utanediol, the dicarboxyli~ acid component (b) comprises from abou~ 60 to abou~. .00 mole percent dimethyl terephthalate, and the ~olyoxyalkylene diimide diacid component (o) iQ derived from trimellitic anhydcide and a polyoxyalkyl diamine selected from the group consisting of polypropylene oxide diamine and a capoly(eehylene oxide-propylene oxide) diamine having predominantly polyethylene oxide in the backbone.
The preferred rubbery alkyl acrylate is based on repeating units of the ormula:

2-CH ) C=O
OC B .

The preferred crosslinking agent is sodium stearate.
Also contemplated are thermoplastic elastomer compositions further co~prising a filler such as a silica and a pla~tioizer. The preferred compositions comprise componen~ (A) in an amount ranging from about 20 to about 99 part~ by weight and component (B) in an amount ranqing from about 80 to about 1 part by weight based upon 100 pa~s by weight of (A) and (B) together.

.- ~ . - ,, . . :

-: . -~ CP-12040~

Also according ~o the presen~ invention, t~ere is provided a process for producinq a thermoolastic elastomer composltion comprising:
( r~ mixinq (i) 3 polyetherimide ester copolt~mer, and (ii) ~ rubbery alkylacrylate; and (II) curing the mixture obtained in step (I) by addin~ a croSSlinKing agent.
Preferably, step (II) of the proces~ ~urther comprises adding an accelerator such as sulfur, sulfur donocs, maqneYium oxide, tertiary amines and mixtures of any o~ ~he foreqoing. ~ost preferred are quaternary ammonium compounds~ -DETAILED DESCRIPTION OF THE INVENTION
.
The polyetherimide esters useful in the p~ac~ice of the pre~ent invention may be prepared ~rom one or more diols, one or more dlcarboxylic acids and one or more high molncular weight polyoxyalkylene dilmide diacids. Preparation of such materials is de~cribed in detail in U.S. Patent No. 4,556,705 of R.J.
McCready, i~Rued December 3, l985 and hereby incorporated by reÇerence.
The poly~etherimide e~ters) used herein may be prepared by conventional processes, such as esterification 2S and condensation reactions for the production of polye3ters, to provide candom or block copolymers.
Thus, polyetherimide esters may be generally characterized as the reaction product of the aforementioned diols and acid~.
Pre~erred compositions encompassed by the preqent invention may be prepared from (a) one or more C2-Cl5 aliphatic or cycloaliphatic diols, (b) one or more C4-C16 aliphatic, cycloalipha~ic or aromatic dicarboxylic acids or eqter derivatives thereof and (c) one or more polyoxyalkylene diimide diacids. The amoun~

CP-I20 ~ 3 of polyoxyalk~lene aiimlde diacid employed is qenerall~
dependent upon the deqired ~roperties of the cesultant polyetherimide estec. ~n genecal, the weight ~atio of polyoxyalkylene diimide diacid (c) to dicarboxylic acid (b) is from aboue 0.25 to 2.0, preferably ~rom about 0.4 to abou~
Suitable diols (a) for use in preparing the compo~itions o~ the present invention include saturated and unsaturated aliphatic and cycloaliphatic dihydro~y compounds a3 well as aromatic dihydroxy compounds.
These diols are preferably o~ a low molecular wei~ht, i.e. having a molecular weight of about 250 or less.
When used herein, the term "diols" and "low molecular weight diols~ should be construed to include equivalent ester forming derivatives thereof, provided, however, that the molecular weight requirement pertains to the d~ol only and not to its derivatives. Exemplary of ester forming derivatives there may be given the acetates of the diols as well a~ for example ethylene oxide or ethylene carbonate for ethylene glycol.
E pecially preferred diols are the saturated aliphatic d}ols, mixeures thereof and mixtures of a saturated diol(s~ with an unsaturated diol(s), wherein each diol contains from 2 to about 8 carbon atoms.
Where more than one diol is employed, it is preferred that at leaqt about 60 mole ~, based on the total diol content, be tha same diol, most preferably at least ~0 mole ~. A~ mentioned above, the preferred compositions are tho~ in which 1,4-~utanediol is preqent in a predominant amount, most preferably when 1,4-butanediol is the only diol.
Dicarboxylic acids (b) which are suitable for use in the practice of the present inYention are aliphatic, cycloaliphatic~ and~or aromatic dicarboxylic acid~. These acids are preferably of a low molecular : : ~ . : : . . , - .
: : ,, ~ . :
. . :: . : . . . : -, , _7_ (8~P-120~0) -~ 2~3110~
weight, l.e., hav1n~ a moleculac wei~ht of 1ess than 3bout 300: however, ~igher ~olecular weight dicacboxylic ac~ds, e~peclally dimer ~cids, may also be used. ~he term "dicar~oxylic acids" 3S used herein, includes S equivalenes o~ dicarboxylic acids havin~ two functionaL
carboxyl groups which perform substantially like dicarboxylic acids in reaction with glycols and diols in forming polyeqter polymers. These equivalents include esters and eqter-forming derivatives, such as acid halideq and anhydride~. The molecular weight preference, mentioned above, pertains to the acid and not to its equivalent ester or ester-forming derivative.
Preferred dicarboxylic acids foc the ~preparation o~ the polyetherimide esters o~ the present invention are ehe aromatic dicarboxylic acids, mixtuces thereof and mixtures of one or more dica~boxylic acids with an aliphatic or cycloaliphatic dicarboxylic acid, most preferably th~ aromatic dicarboxylic acids. Among the aro~atic acids, those wiéh 8-16 carbon atoms are preferred, particularly the benzene dicarboxylic acids~
i.e., phthalic, terephthalic and isophthalic acids and their dimethyl derivatiYes. Especially preferred is dimethyl terephthala~e.
F1nally, where mixtures of dicarboxylic acids are employed in the practice of the present invention, it is pre~erred that at least about 60 mole ~, preferably at least about 80 mole ~, based on 109 mole o~ dicarboxylic acid (b) be of the same dicarboxylic ac-d or ester deriYative thereof. As mentioned above, the preferred compositions are those in which dimethyl-tereph~halate is the predominant dicarboxylic acid, most preferably when dimethyl terephthalate is the only dicarboxylic acid.
Polyoxyalkylene diimide diacids (c) suitable for use herein are hiqh molecular weight diimide diacids '' " . '~' ' ' :, ~ ., ~ .

~ CP-IZ0~0) 203~
~hereln the average molecular ~eiqht is greater than about 700, most ~refera~ly grea~er than about 900. ~hey may be prepared by the i~idization reaction of one or more tricarboxylic acid comPounds containing two ; vicinal carboxyl groups or an anhydride group and an ~dditional carboxyl qroup which must be esterifiable and pceferably is nonimidizable with a high molecular weight polyoxyalkylene diamine. ~he polyoxyalkylene diimide diacids and processe~ for their preparation are more ~ully disclosed in copending U.S. patent application Ser ~.~o. 665,192, filed Oct. 26, 1984 entitled "~igh Molecular Weight Diimide Diacids and Diimide Diestees o~
Tricarboxylic Anhydrides", incorporated herein by reference.
rn general, the polyox~llkylene diimide diacids useful herein may be char.?~:~terized by the following formula:

O O

R'OOC-R N-G-N \R-COOR' \C / \C/
Il il : -O
~ :, wherein each R is independen~ly a trivalent organic cadical, preferably a C2 to C20 aliphatic, aromacic or cycloaliphatic trivalent organic radical; each R' is independently hydrogen or a monovalent orqanic radical preferably selected from the group consisting of Cl to C6 aliphatic and cycloaliphatic radicals and C6 to C
aromatic radicals, e.g. ohenyl, most preferably hydrogen: and G is the radical remaining after the removal of the terminal (or as nearly terminal as possible) hydroxy groups of a long chain ether glycol having an average molecular weight o~ from about 600 to . , . ~ ,, : .; . -: .
.
.
. .

~ CP-L2040) . . , ~V31~0~
about 12000 ~refe~aoly from about ~00 to about 4000 and a carbon-to-oxygen catio of about 1. a to about 4.3.
Represeneative long chain ether ~lycols from which the polyoxyalkylene diamine is pcepared include poly~ethylene ether)glycol; poly(propylene ether) glycol;
poly~tetramethylene ether)g'lycol; random or block copolymers of ethylene oxide and propylene oxide including propylene oxide terminated poly~eth~lene ether~glycol; and random or block copolymers of ' te~rahydro~uran with minor amounts of a second monomer such as methyl tetrahydrofuran (used in proportion such that the cacbon-to-oxygen mole ratio in the glycol does not exceed abou~ 4.3). Especially preferred poly(alkylene ether~glycols are poly(propylene ether)glycol and lS poly~ethylene ether~glycols end capped with poly(propylene ether~glycol or propyle~e oxide.
In general the polyoxyalkylene diamines u~eful within the scope o the present invention will have an average molecular weight of from about 600 to 20 12000 preferably from about 900 to 4000.
T~e tricarboxylic component may be almost any carboxylic acid anhydride containing an additional carboxylic group or the correspondin~ acid thereof containing two imide-forming vicinal carboxyl groups in ~ :
lieu o~ the anhydride group. Mixtures thereof are also suitableO The add$tional carboxylic group must be ~
eqteriflable and preferably is substantially 1:
nonimidizable.
The tricarboxylic acid materials can be characterized by the following formula~

R'OOC-R/ \ O
\ C / ~ '~
Id . .. ., . ,. . . ;

..
,: ~ :.- ' , ` : :
: . : ~ . . . : ::
: :: :
~. ~
~ ~: ` . ' :, ' ' ' ' :.
: . . ... . . . . .

-!0- (~CP-12040) 203~0a ~nere R is a trivalen~ organic radical, ~referably a C2 to C20 aliphatic, aromatic, or cycloaliphatic tri~alent organic radical and R' is ~referably hydrogen or a monovalent or~anic r~dical ?referably selected ~rom the S group consisting o~ Cl to C6 aliphatic or cycloaliphatic radicals and C6 tO Clz aromatic radicals, e~y. phenyl;
most preferably hydrogen. A preferred tricarboxylic component i5 trimellitic anhydride.
ariefly, these polyoxyalkylene diimide diacid~
may be prepared by known imidization reactions including melt synthe~is or by synthe3izing in a solvent system.
Such reactlons will generally occur at temperatures of from 100 degrees C to 300 degreec~ C, preferably at from about 150 degrees C to about 250 degrees C while drawing off water oe in a solvent system at ~he reflux temperature o the solven~ or azeotropic (solvent) ~ixture.
Although the weight ratio of the above ingredients i not critical, it is preferred that the 20 dlol be presen~ in at least a molar equivalent amount, ~
preferably a ~olar excess, most pceferably at least 150 ;~-mole ~ ba~ed on the moles of dicarboxylic acid (bt and polyoxyalkylene dlimide diacid (c) combined. Such molar ex~e~ of diol will allow for optimal yields, based on 25 the amount of acidc2, while accounting ~or the loss of ~ :
diol during esteriflcation/condensation.
Purther, while the weight ca~io of dicarboxylic acid (b) to polyoxyalkylene diimide diacid (c) is not critical to ~orm the polyetherimide esters used in the pre~ent i~vention, preferred compositions are those in which the welght ratio of the polyoxyalkylene diimide diacid (c) to dicarboxylic acid ~b1 is from about 0.25 to about 2, preferably from about 0.4 to about 1.4.
The actual weight ratio employed will be dependent upon the specific polyoxyalkylene diimide diacid used and .. , . ~ ~ :
.~" -', ' . . : ~
,~

~ 5~CP-~20~0) 2~311~
~ore lmport~ntl~ e de~i~ed physical and chemical proper~i s o the ~esultant polyethecimide eqter. rn qeneral, ~e lower ~e ~tio Oe poi~ox~alkylene diimide diester to dicarboxylic acid the bs~ter S strength, crystallization and heat distoetion proDecties o the polymer. Alternativ~ly, the higher the ratio, the better the ~lexibilit-~, tensile set and low temperature impact characteristics.
In preferred embodiments, the polyetherimide es~er product will comprise the reaction product of dimethyl terephthalate, most preferably, with UD to 40 mole ~ of anothec dicarboxylic acid; 1,4-butanediol, optionally with up to 40 mole ~ of another satura~ed oe unsaturated aliphatic or cycloaliphatic diol; and a polyoxyalkylene diimide diacid prepared from a polyoxyalkylene diimine of molecular weiqht of from about 600 to about 12000, preferably from about 900 to 4000, and trimellitic anhydride. In its most preferred embodiment , the diol will be 100 mole ~ 1,4-butanediol and the dicarboxylic acid 100 mole ~ dimethyl terephthalate.
The polyetherimide esters described herein may be prepared by conventional esterification~condensation reactiOnS ~or the production of polyesters. Exemplary of the pcoces es that may be practiced are as set forth in, for example. U.S. Pat. Nos. 3,023,192, 3,763,109 3,651,014, 3,663,653 and 3,801,547, herein incorporated by reference. Additionally, these compositions may be prepared by such prooesses and other known processes to efect random copolymers, block copolymers or hybrids t~ereof wherein both random and block units are present.
It i~ customary and preferred to utilize a caealy~ in the process for the production of the polyetherimide esters of the present invention. In general, any of the known ester-interchange and : . ~ ., ,,- : :

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-l2- (8CP-12040) ,,, ~3~
?olycondensa~on c~tal~sts may be used. Although t"o seoarate catalysts oc catalyst sys ems may be used, one for es~er intecchange ~nd one for pol~condensation, it is preferred, where aDproDriate, to use on~ catalyst or S catalyst system for ~oth In those instances where t~o separate c~talysts are used, it is oreferred and advantageous to render the ester interchange catalyst ineffective following the completion of the preconden~atlon reaction by means of known catalyst inhibitors or quenchers, in particular, phosphorus co~pound~ such as phosphoric acid, phosphenic aoid, phosphonic acid and the alkyl or aryl e~ters of salts thereof, in order to increase the thermal stability of the resultan~ polymer.
Exemplary of the suitz~!e known cataly~ts there may be given the acetates, _arboxylates, hydroxidas, oxide~, alcoholates or organic comple~
compound~ o~ zinc, manganese, anti~nony, cobalt, lead, c~lcium and the alkali metals insufar a~ these compounds a~e soluble in the reaction mixture. Specific examples include, zinc acetate, calcium acetate and combinations thereof with antimony tri-oxide and the like. These cataly~es aq well as additional useful catalysts are described in U.S. 2~t. No~. 2,465,319; 2,534,023:
2,850,483; 2,892,871; 2,937,160; 2,998,412; 3,047,539;
3,110,693 and 3,385,330, among others, incorporated herein by reference.
Where the ceactants and reactions allow, it is preferred to use the titanium catalysts including the inorganic and organic titanium containing catalysts, quch as tho~e de~cribed in, for example, No~. 2,720,502;
2,727,881; 2,729,619; 2,822,348: 2,906,73~; 3,047,515;
3,056,817~ 3,056,818; and 3,075,952 among others~
incorporated herein by reference. 2specially preferred are the organic titanate~ such as tetra-butyl titanate, ..... .
. , : . ~ . : :-;

.

-l3- ! ~CP-I 2040 ) ~31~ ~
eetra-isopropil t~ ~na~e and tetra oct~1 titanate 3nd the complex titana~es deri~ed ~rom alkali oc ~lkaline earth metal alkoxldes ~nd titanate esters, most preferably the oc~an~c ti~anate3. These too may be used alone or in co~bination with other catalysts such as for example, zinc acetate, man~anese acetate or antimony trioxide, and/or ~ith a catalyst quencher as described above.
Although these polyetherimide esters possess many desirable properties, it is often preferred to stabilize the compositions to heat, oxidation, radiation by UV light and the like, as d~scribed in the aforemeneioned U.S. Patent No. ~1,556,705.
The polyacrylate elastomers or ru~bery alkylacrylates are generally copolymers having two major componen~s: the backbone, comprising from about 95 to about 99 weight percent of ~he polymer; and the reactive cure site, comprising ~rom about 1 to about 5 weight percent of the polymer. Preferably the copolymers have hlgh molecular weights, typically around 100,000 Mv tvisco~ity average molecular weight). The backbones are made ~rom monomeric acid esters to form repeating uni~s of pri~arily two types:
.:
2-C~ + or+ C~2-CH~
C~O ~=0 , ,~
O-CnH2n+l n 2n m~2m~

where n is 2 or 4 and m is 1 or 2. The most common cure site monomers are 2-chloroethyl vinyl ether and allyl -~
glycidyl ether. Physically, polyacrylate elastomers are inherently soft and tacky. They commonly have celatively low Mooney viscosities (ML-1+4 @ 100C) in 3n the 2S to 60 range. These elastomers are more fully de~cribed in P.H. âtarmer and F.~. Wolf, Encyclopedia of ,. - - .

. ~ : : : . ~ :-:: . , , -14- (~CP~

Polymer Science and Engineering, Z~ Ed., 306-325 (1985), incorporated hereln by reference.
The mixing o~ the polyetherimide esters and polyacrylate elasto~ers may be carried out in any device S known to those skilled in the art. Preferably the components are melt ~ixed in a compounding device such a~ an internal mixer (Brabender or Banbury type) and extrudecs (twin screw or kneading). The polyetherimide ester and polyacrylate elastomers are typically cambinable in pcoportions canging erom about 20 to about 99 parts by w~ight ?olyetherimide ester and from about 80 to about 1 part ~y weight polyacrylate elastomer based upon 100 parts by weiqht of the two resins combinedO Pre~e~ably, the polyetherimide ester is pcesent in an amount ranging ~rom 20 to about 80 parts by weight, mo~t preferably ~rom about 40 to about 60 part~ by weight; and correspondingly the polyacrylate elastomer is present in an amoung ranging from about 80 to abou~ 20 parts by weight, most preferably from about 6n to about 40 parts by weight. In another pceferred e~odiment the compositions oÇ the present invention comprise about S0 par~s by weight polyetherimide ester and about S0 pares by weight polyacrylate elastomer.
The mixing compositions may also contain, in addition to reRin and rubber, variou~ additives known to those skilled in the art for use in compounding o~ -thermoplastics, rubbers, and their blends, to modify the propertle~ thereof, such as, but not limited to fillers, stabilizer~, antidegradents, processing aids, plasticizers, pigments and the like. Typical fillers would include carbon blacks, silicas, clays, minerals or mixtureq threof. 8Oe~ low and hi~h molecular weight plast~cizer2 are contemplated.
In a typical composition, the crystalline -~
thermoplastic copolyetheri~ide ester re~in, rubber and - '' 7 - ~ ~ C P - ! 2~4 ~dditives ace mlxed La the appropriace de~Jice at temperature high enouqh to 30ften and/or melt the materials such that ~n intimate mixture is obtained~
Once an intimate mixture is obtained, the ~ubber ma~erial is cured hy the addition of ccosslinking agents, and optionall~ accelerators.
C~csslinking agents are any agents which promote vulcanization of the acrylic elastomer. The cure sy~tem employed varies with type of cure-site ~onomer ptesent in the ac~ylic elastomer. Preferred crosslinking agen~s are soaps including metallic carboxylate3 such a~ sodium or potassium stearate, Optionally the cure system may ~lso com~rise an accelerator ~ well as a crosslinking agent. Pre~erred acceleratocs i~clude sulfur; sulfur donors such as tetramethylthiouram: or bases such as magnesium oxide or tertiary a~ines. Ammonium benzoate, a~monium adipate, and soap/quaternary a~ine systems are also known to be effec~ive cure systems, as are red lead/ethylene thiourea and diamines and polyamines. Most preferred is a soap~qua~ernary ammonium system. These and others are more extensively discussed in the above-reference Starmer ne al. article.
Mlxing time is determined by the temperature `
2S and/or amounts o f crosslinking agents added. The ~aterial~ thus produced are processable by common thermopla3tic processing techniques, such as injection and co~pression molding techniques and yield flexible, ela~tomeric pare~. ~
DESCRIPTION OF T~E PREFERRED EMBODIMENTS ;
~he followinq examples illus~rate the present inYention. They are not to be construed to limit the claims in any manner whatsoever.

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-16- (~CP-12040) ~03~
-XAMPLES 1~3 To a BraDen~er mixer are added 42.6 g of a polyacrylate elas~omer (100 pnr~, 23.4 g of a pol~ther-imide ester (66,7 pnr) and 0.43 g (1 phr) o~ an antioxidant (Irqanox~ 1010). The mixture is mixed and heated to ~orm an intimate blend. ~nce an intima~e blend is obtained, 1.70 g (4 phr) of a crosslinker (sodium stearate) and 0.85 g (2 phr) of an accelecator (NPC-50) are added. The mixture is dynamically cured for 2 to 3 minutes and the composition is compression molded into te~t specimens and tested for tensile strength properties according to ASTM D-412. For comparative purposes, ~ests are run without curin~. The .
re~ults along with compositional data are set forth below in Table 1.

.. .. . ..

c ~c ~ O~C~12040) ~ ~ 7--D ~ I I u^ C~ l 2 ~) 3 1 1 ~ O
r r r ~ ~
~r ~ C
r c ~o _ _ _ ~ l l l I
~ ~ q~
~ r~ r D
O U It~

, O

r`J I II ~r u C r'~ ' u~ ~ r . r ~ 0 o c co , u _ , 2 _ 1 ~_ Q
~: ~ ~O ~
a ~
u .s u ,_ ~ ~r ~ In o ~ ',~r O ~ ~J
E~ Z o ~
O O u~ _ _ . ~ E
~ ~ O O O O ~
U I_ _ - _ _ ~ U ::
t~l ~ u~ U t~ U
1:~. . . ~ ~ . c t~ ~r ~ o _ o c ~ u -~ U U U ~ ' ' E~
r S ~ ~ ~ L~
~ ~D ~ t.) O '-C~
_ _ _ O ~ Ll ~ _~ ~ I I I I ~

~ ~ O ~ ~ L~ -- -- -- U
a~ ,C
E L~
~J o ~ Q~ ~ E
,~
E n~ C
~P~a ~ o a~
E
~: al ul ` ~ ~ ~1 ~ 1 E n~
E E E
C c~ ~ C L~ U ~ ~ ~ E
_- ~ U~ O
~1 .- O U ~ x ~J ~ ~ E ~
_ U~ (~ ~ ~ O L! _I ~ O ~ O O O ~ O
E~ O E _- N Ul ~:: U~ C . U CL ~ ~ Cl. a u~
al E ~ ~ ~ U Cl C1- 0 C o ~c o ~ ~ ~ ~ ~ ~ a~ _, . Z Z ~ ~ E~ ~ x ~ n u ~;

. .

-13- (~CP-12040) r t can be seen from Table 1 above that 2 C~ 31 l- O ~
dynamically curing t.~e polyetherimide ester vastly improve~ t~e tensile bceak strength with a minimal decrease in elongation break. (Example 3 vs. 'A~). In the polyetherester examples, curing improved the ~ensile break streng~h.

, . . .
The procedure of Examples 1-3 is repeated except employing a Banbury mixer and various other additives and the concentration o~ a filler is varied.
The compositions are then injection molded into ASTM
D-412 Type l bars. The cesults along with compositional data are set ~orth in Table 2 below.

-19- (0~3C~12040) ", ~ 0 ~

o r~
O ~ ~n o o o ~ ~ o ~ u~
1-- O O ~ I C Q ~ ~ O U) _ C
~ CW ~ O _ a~

O ~
O O` U~ O O
C ~ o o c t~l ~ h O ~.0 111 . . ~ ~ .. ~ IJ~ ¢ _ ' ::~
~O ~ ~ . _u~ ` C ~ ~ I` I 1~ ~ ~ ' ~ O

~: I O
t~l aJ
~ _. ~ O _~ , tLl ~ n o ~ ~ u ~ ~ .n a~ O u~ I` ~ ~ ~ o ~ a~
¢ E~ ¢~ ~ ¢ ~ ~ U~
t~ U~
O o O O O u~ 0 O
o ,n o o o C o o ~ el~ ~
O O O ~ O u~ O
~r a~ E ~J ~ c r S h7 C.) C L~
C ~ C U.7 ~.
O ~ O
¢ U ! e!J c L. o I u o ~ o m ~ o c:~ I ~ u.7 _~ I
o C~ E J ~a ~ ~
IJ ~J O
u7 CP co ~ ~ c o E~
d~ U7 0 '3 --~ ~ S U~

t7 Ul ` ~ ,J tJ ~ 1~1 ~
o ~ ` ~ u7 :~ al -' C C O
h7 O r` ~ ~ .
~ a~ ~ o ra .~ 5 c ::~ U.7 U'~
C u- V7 O ~ O 1~ C C I L~ S
O o 3 c ~ r~ n ~ C O ~ O O I t .. 4 ~ ~ ~7 0 ~ ~ J U~
.LJ O aJ ~ ~ ~~ u u~ U7 1 ~ ~ O
~ ._. O ~ ~ X O IJ C.J -1 U7 0 C ~ ~-~ U7 U7 ! ~ u _~ U7 CL ~ O O -~ O ~ ' _~ rc7 - ~ C O ~ Ql I O O /~
t~ O E JJ ~l -- ~ C I ~ c~ ~
E CL ~ h7 `' U) U~ U~ C C oP l~ U~ ~ U a.
~ ~ ~ U 1~ 0 ~: O ~ O ~ ~ O ~I E ':: 11 1I 11 11 11 X O :~ h7 J~ . ~ O L~ ~) ~-1 O O ~ CJ C Cl~ O O
t~7 U ~ ~ U~ Z U7 ~ E~ tL7 ~ n ~ U~ U7 U U ~I 8 ~S al U

,, : ., . ~ . , ,: .

,', ,: ' ~ '. - ,: . : ,` .. ' ' : .. . .
. ' ' ,: ' '. ~' ,., :, : ,: : . -. -20- (~CP-1204~) _XAMPLES 8-12 ~0 3 1 1 0 V
The procedure o~ Example; 4-7 is repeated excep~ var lOUS other additives are employed and t~o different ?lasticizers are employed at t~o concentration levels (2.5 and 5.0 phr). The results are set forth in S T~ble 3 below.

~- : . ., ~ . --21- (0~ 120~0) ~311~
C ~
C ~ C -- C --C C C ~ ~ ,o C C ~ ~ r~ 1 0 ~ ~ ~ C r~ ~~C ` c C ~ ,.
o o~ C o o U~
o C ~. U' o o ~ o ~o , o ~o U~ . ~ ~ . . ~ , ¢
co In a~ ~ ~ 0 a~ ~1 ~ ~ ~ ~ _ o C o o o .O C C C ~ ~D O O -- ~D
o o oer .~ ~ . . . ~ ~ . ~ _ ~:
U
E~
,~ U~ o Ul ~: o o~ o C~ o Ul .~ . . o o ~ u o o ~ ~ u~ r o ~
~D a~ ~ ~ r~ I o ~ r~ ~ ~r In ~ O ~
E~

o ~o ~ .
o ~ o o o U~

I~ U oO : ' ~
a~ ~7 o _. ~

dP 01Cl. ¢

CL V ` ul u~
o ~ n o m C U~ V~ ~ o ~ C
O o 3 ~ ~ ~C 0 ~c o ~ O O
_ ~ ~ ~ IaJ t~ O ~ ~ IJ U~ T .~J _ .' ~ h _~ O U~ X aJ '~ '' ~ n~
ID ._ ~ U"l X ~ J a) ~ o c ~ 11) _~ ~ CL ~ O _ O OE~ 0 L~ ~ ~ o ~ ~ ) O E ~ ~
E O. c~ b~ Y tl) Y~ I ~ - u~ c C *~ U Q. Cl.
~ e ~ ~ u ~ o c o~ o ,~ c o c~ E E
X O ~ ~ ~ ~ O n~ _~ ~al ~ o o JJ a~ c Q~ O
t~ u ~ n T E )--4 Z U~ ~ ~ aL ~ U U :

-22 (~CP~1204~) -A~LE ~ (sontinued~ ~ 31 10~

a = Polyacrylate elas~omer (Zeon Chemicals Co.) = Polyethecimide estec (General Electrio Co.) A = Failed during initial straining at 100 B ~ Failed during hold at ioo% strain according to ASTM D395-B foc 22 hours, average value o~ fouc runs ~,:, ' -:: - ;, ..

r-- 23 (8CP 12040) ~XAMPLES 13-1~? ~3 Lhe oroceduce Oe rxamples 4-7 is repeated except varlous ochet additives are employed and the rubbec/resln weiqnc .~tio is varied at 20/B0, 40/60, ;0/50, 60/40 and ~0/20. The results alon~ with compositional data ace set forth below in Table 4.

~ u~12040) C ~ c c c~ c 2~31~ ~
c r ~
_ ~ _. r~ r r~

C: C
C ~ o O c C O C C C ' 3 ~ c oc ~ u~
_ c C~ u~ ~ r~l u u~ u O O
o u~ O O ~
o r~ o o r ~ ~ O r~ _ UO
_. ~ ~ o ~ O O cn c:~
r~ 1~ r ~ rJ ~
O

~ C~ O
er ¢ O U~ O O C r~
~ ~ r~ co r~ rJ
t~l ~ ~ Cl O
_ _ ~ . N ~ r~
~_ ~ a~ q ~ r~
~1: U~
E~ c.~
C~:
,.. , .~ .
t,~
a~
O
C~ Cl ~: o n u~ o r~
m ~ ~ 1 r~ o ~ ,_ ~ . . . . . r~ rJ ~r ~ ~ ~n ~ ~D
.

, ",~ ~10 c" ~
:,, :-r~ C ~P

-- ~ I -- )~ V ~ 0 ~ ~ -c u tn ~ o ~ ul 1) ~ 3 O o 3 ~ ~. ~ C O
_ ~ ~ ~ ~:o o v ~ x .~ h .,, .~
._ ~ X ~ ~ O J- ~1 0 0 ~ C
0 ~ o _ o o e ~ u ~ c o C~, g E ~ ~ C Lr~ :~
E C~ a~ tl ~1 u~ C C oo c~ U Ul E~ v ~ ~ J ~ O ~ C O ~ o o L~ C
~: O ~ ~ ~ J ~ O ~ ~ ~ ~ O O O Q~ aJ
~ u ~ ~ ~ ~ Z ~n ~ ~ E~

:: ~ :- - - ' - . :' r- I (~3CP-120~0) 3 i. '1 ~) 3 ,, . ~ ~ . ~o I I , 30~

~J
aJ
~ _. 1 Ul ~ O U~
_ c~
_. _ ~ ~ r _ U' ~ ~ .
C O aJ
._.
C ~ C ~
O ~r O ~ ~ u~
U _ ~ ~ o ~ ~ ~ ~r ~ Q, _ ~ ~ ~
~r ~ Q~
_ . E o ¢ O u c E
~4 . U -~ C
~ ~ U7 o U~ _ ~ U
~ U~ o ~ _ _ U
_ a~ D ~ E a~
_ _. _ _ _ ~ c~ _~ E ~
o 3 U u E
_ o C ~ U~ U
O ~ (3 N C C
" ~ E~
co E u x C
Ul ~ _~ X
u ¢ ~ E
t~. Y ` u~ u -' E
~ E c ~
C , . ~
~ o ~
u~ ~ ~ ~ ~ ~- s a~
~ a~ o ~ u n .~ ~q ~. ,.
aJ ~ ~ ~ o o U~ _ _- o ~
_. ~ ~ C ~ o o U --.~ C' ~ C~
E ~ u~ c c C o ~ o C~ ~ ~. 11 11 11 x :~ a~ -- o o o aJ ~
.~ E~ ~ a~ 5 ~ O
:, ` : , . , : .
: ., : ~, :

::.: : : ::: : :':` . ~
.. . . .
,:.. . . . . . :
. :: : : ' -25- ~CP-l2~40) .com ~he aoove T~bles l-~ it can be seen ~at~
the physical propectL~s o~ a typlcal comoosition containing 60 par~s b~ ~elaht cubber ~nd 40 parts by weight crystalline ~.~ermo~las~ic Dolyetherimide ~ster S and a suitable additlves package are: Tension Set (ASTM
D412) typically IS to 25 per.cent: Compression Set (ASTM
D395 Method 3 plied sample) approximately 16 perc~nt at 23C~22 hours and 45 percent at 100~C/22 hours.
Hardness value.~ (Shore A durometer) of 55 to ~0~ Doints 1~ can be achieved by suitable choice of comoonents and additives.

T~e composltions of the present invention are placed under Dynamlc .~echanical Thermal Analysis (DMTA) to produce DMT~ curves. Typical thermoplastic materials, such as the crystalline thermoplastic elastomers u~ed hecein, exhibit storage modulus versus te~pe~a~ure OMTA curves which can be described as possessin~ a glassy plateau which is generally constan~
in magnitude, followed by a glass transition region which is characterized by a two to three order of magnitude dr~p in the s~orage modulus to the so-called ~:
rubbery plateau. The cubbecy plateau-storage modulus value is then usually observed to decrease with increasing temperature in thermoplastics (i.e. viscous flow). In semi-crystalline thermoplastics the rubbery plateau is then followed by a large drop o~f a~ the crystalllne melting point of the polymer.
rn the compositions of the present invention, -the drop off of modulu-~ associated with the meltin~ of the polyetherimide ester is observed to be followed by what may bs termed a second rubbery plateau which was found to be af constant magnitude to the exten~ of the ~emperature teseed (250C). The pcesence of this second cubbery plateau was found to be dependent on the ratio ,.,. : : . , " ,,:

: :

-27- (~CP-120~0) - 20311~
o~ ~IDber ro t~ermoolas~ic ~ h compositions havin~
below 50 welght ?ercent ~ubber not exhibiting the second ~ubbery plateau. n a thermoset ~ubber material, the s~orage modulus would be essentially constant in the ~ubbery ?lateau ~eqion and would not ~rop off ~ith increasinq tempera~ure (until degradation occurs), due to ccosslinkin~ o~ the system.
To eest ~he thermoplasticity o~ the compositions a typical material which exhibits the second rubbery plateau was prepared, molded and then heated ~or 75 minu~es ac 200C ln an air circulating oven.' The material is then charged into a Brabender mixer and mixed to a molten state in which the consistency was observed to be constant ~s a function o~ time over a ten minute te~t period.
Thus, ehe materials are thermoplastics. rf the materials were becoming thermoset above the meltinq point o~ the ccystalline thermoplastic polyetherimide e~ter, they would have shear degraded when ceprocessed as doe3 a true thermoset material.
The above patents, patent applications, publications and ~es~ methods are hereby incorporated by reference.
~ any ~ariations of the present invention will sugges~ them~elve~ to those skilled in the art in light of the above-detailed description. For example, any ;
polyetherlmide e~ter resin and alkylacrylate elastomer may be employed. Other suitable crosslinkers and accelerators are also contemplated. ~dditives such as ~lame re~ardants, light stabili~ers and the lîke ~ay be employed in the compositions of the present invention.
All such obviouq modifications are within the ~ull intended scope o~ the appended claims.

..... .
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: : , : .
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,: : : ,:., . ~ ~ . :

Claims (36)

1. A thermoplastic elastomer composition comprising:
(A) a polyetherimide ester copolymer;
(B) a rubbery alkylacrylate, and (C) a crosslinking agent.

2. A thermoplastic elastomer composition as defined in Claim 1 wherein said polyetherimide ester copolymer comprises the reaction product of (a) one or more low molecular weight diols; (b) one or more dicarboxylic acids; and (c) one or more polyoxyalkylene diimide diacids.

3. A thermoplastic elastomer composition as defined in Claim 1 wherein said diol component (a) comprises from about 60 to about 100 mole percent 1,4-butanediol.

4. A thermoplastic elastomer composition as defined in Claim 2 wherein said dicarboxylic acid component (b) comprises from about 60 to about 100 mole percent dimethyl terephthalate.

5. A thermoplastic elastomer composition as defined in Claim 2 wherein said polyoxyalkylene diimide diacid component (c) is derived from one or more polyoxyalkylene diamines and one or more tricarboxylic acid compounds containing two vicinal carboxyl groups or an anhydride group and an additional carboxyl group, and is characterized by the following formula:

wherein each R is independently selected from the group consisting of C2 to C20 aliphatic and cycloaliphatic trivalent organic radicals and C6 to C20 aromatic trivalent organic radicals; each R' is independently selected from the group consisting of hydrogen, C1 to C6 aliphatic and cycloaliphatic monovalent organic radicals and C6 to C12 aromatic monovalent organic radicals; and G is the radical remaining after removal of the hydroxy groups of a long chain ether glycol having an average molecular weight of from about 600 to 12000.

6. A thermoplastic elastomer composition as defined in Claim 5 wherein said polyoxyalkylene diimide diacid is derived from trimellitic anhydride and a polyoxyalkyl diamine selected from the group consisting of polypropylene oxide diamine and a copoly(ethylene oxide-propylene oxide)diamine having predominantly polyethylene oxide in the backbone.

7. A thermoplastic elastomer composition as defined in Claim 1 wherein said rubbery alkylacrylate consists essentially of repeating units of the formulae:

and where n is 2 or 4 and m is 1 or 2 and a cure site monomer.

8. A thermoplastic elastomer composition as defined in Claim 7 wherein said rubbery alkylacrylate is based on repeating units of the formula:

9. A thermoplastic elastomer composition a-defined in Claim 1 wherein said crosslinking agent is elected from the group sodium stearate, potassium stearate and a mixture thereof.

10. A thermoplastic elastomer composition as defined in Claim 1 wherein said polyetherimide ester component (A) comprises from about 20 to about 99 parts by weight and said rubbery alkylacrylate component (B) comprises from about 80 to about 1 part by weight based upon 100 parts by weight of (A) and (8).

11. A thermoplastic elastomer composition as defined in Claim 10 wherein said component (A) comprises from about 20 to about 80 parts by weight and said component (B) comprises from about 80 to about 20 parts by weight.

12. A thermoplastic elastomer composition as defined in Claim 11 wherein said component (A) comprises from about 40 to about 60 parts by weight and said component (B) comprises from about 60 to about 40 parts by weight.

13. A thermoplastic elastomer composition as defined in Claim 10 wherein said component (A) comprises about 50 parts by weight and said component (B) comprises about 50 parts by weight.

14. A thermoplastic elastomer composition as defined in Claim 1 which further comprises a filler, a stabilizer, an antidegradent, a processing aid, a plasticizer, a pigment, or mixtures of any of the foregoing.

15. A thermoplastic elastomer composition as defined in Claim 14 wherein said filler is selected from the group consisting of carbon blacks, silicas, clays and minerals.

16. A thermoplastic elastomer composition as defined in Claim 14 wherein said plasticizer comprises a low molecular weight plasticizer or a high molecular weight plasticizer or both.

17. A process for producing a thermoplastic elastomer composition comprising:
(I) mixing (i) a polyetherimide ester copolymer, and (ii) a rubbery alkylacrylate; and (II) curing the mixture obtained in step (I) by adding a crosslinking agent.

18. A process as defined in Claim 17 wherein said polyetherimide ester comprises the reaction product of (a) one or more low molecular weight diols; (b) one or more dicarboxylic acids; and (c) one or more polyoxyalkylene diimide diacids.

19. A process as defined in Claim 18 wherein said diol component (a) comprises from about 60 to about 130 mole percent 1,4-butanediol.

20. A process as defined in Claim 18 wherein said dicarboxylic acid component (b) comprises from about 60 to about 100 mole percent dimethyl terephthalate.

21. A process as defined in Claim 18 wherein said polyoxyalkylene diimide diacid component (c) is derived from one or more polyoxyalkylene diamines and one or more tricarboxylic acid compounds containing two vicinal carboxyl groups or an anhydride group and an additional carboxyl group, and is characterized by the following formula:

wherein each R is independently selected from the group consisting of C2 to C20 aliphatic and cycloaliphatic trivalent organic radicals and C6 to C20 aromatic trivalent organic radicals; each R' is independently selected from the group consiting of hydrogen, C1 to C6 aliphatic and cycloaliphatic monovalent organic radicals and C6 to C12 aromatic monovalent organic radicals and G is the radical remaining after removal of the hydroxy groups of a long chain ether glycol having an average molecular weight of from about 600 to 12000.

22. A process as defined in Claim 21 wherein said polyoxyalkylene diimide diacid is derived from trimellitic anhydride and a polyoxyalkyl diamine selected from the group consisting of polypropylene oxide diamine and a copoly(ethylene oxide-propylene oxide)diamine having predominantly polyethylene oxide in the backbone.

23. A process as defined in Claim 17 wherein said rubbery alkylacrylate consists essentially of repeating units of the formulae:
where n is 2 or 4 and m is 1 or 2 and a cure site monomer.

24. A process as defined in Claim 23 wherein said rubbery alkylacrylate is based on repeating units of the formula:

25. A process as defined in Claim 17 wherein said crosslinking agent is selected from the group sodium stearate, potassium stearate and a mixture thereof.

26. A process as defined in Claim 17 wherein said polyetherimide ester component (i) comprises from about 20 to about 99 parts by weight and said rubbery alkylacrylate component (ii) comprises from about 80 to about 1 part by weight based upon 100 parts by weight of (i) and (ii).

27. A process as defined in Claim 26 wherein said component (i) comprises from about 20 to about 80 parts by weight and said component (ii) comprises from about 80 to about 20 parts by weight.

28. A process as defined in Claim 27 wherein said component (i) comprises from about 40 to about 60 parts by weight and said component (ii) comprises from about 60 to about 40 parts by weight.

29. A process as defined in Claim 25 wherein said component (i) comprises about 50 parts by weight and said component (ii) comprises about 50 parts by weight.

30. A process as defined in Claim 27 wherein step (I) further comprises mixing (iii) a filler, a stabilizer, an antidegradent, a processing aid, a plasticizer, a pigment, or mixtures of any of the foregoing.

31. A process as defined in Claim 30 wherein said filler is selected from the group consisting of carbon blacks, silicas, clays and minerals.

32. A process as defined in Claim 30 wherein said plasticizer comprises a low molecular weight plasticizer or a high molecular weight plasticizer or both.

33. A process as defined in Claim 17 wherein said step (II) further comprises adding an accelerator.

34. A process as defined in Claim 33 wherein said accelerator is selected from the group consisting of sulfur, sulfur donors, magnesium oxide, tertiary amines, quaternary ammonium compounds and mixtures of any of the foregoing.

35. A process as defined in Claim 34 wherein the crosslinker comprises sodium stearate and the accelerator comprises a quaternary ammonium compound.

36. The invention as defined in any of the preceding claims including any further features of novelty disclosed.