CA2254973A1 - Thermoformable multilayered polyester sheet - Google Patents

Abstract

A thermoplastic composite comprising an extruded thermoformable self-supporting sheet having an outer decorative chemically resistant and renewable filled polyester layer and an adjacent inner supporting thermoplastic layer for enhancing desirable mechanical properties of the composite.

Description

W O 98/41399 PCT~US98/05108 THERMOFORMABLE MULTILAYERED POL~ SHEET
This application claims the benefit of U.S. Provisional Application 60/041,015, filed March 19,1997 (Our Case 8CT-5680 PA).
Field of the Invention This invention relates to a polyester composite sheet which may be thermoformed into a variety of articles such as bathroom sinks and tubs.
Background of the Invention Filled crystalline resin blends are often difficult to form into profiles or sheet. Crystalline resin has poor melt strength and high shrinkage upon cooling This makes it difficult to obtain thick sections with good dimensional tolerances. Typically, extruded crystalline resins may also exhibit a very rough ~u~a~e.
0 U.S. patent 5,441,997 describes polyester molding compositions which have ceramic like qll~liti~, can be molded into relatively thin sections, and have good impact strength. The composition is directed to a polybutylene terephth~l~te and/or polyethylene terephthalate and an aromatic polycarbonate with inorganic fillers selected from the group consisting of barium sulfate, sL.ol~lium sulfate, zirconium oxide and zinc sulfate. If desired, a styrene rubber impact modifier is described as added to the composition as well as a fibrous glass reillfo~ g filler. Although these compositions are suited for many applications where ceramic like qualities are desired, it is desirable to have even more irnproved and more economical molded structures.
5U.S patent 5,510,398 to aar~, et al describes the use of the non-dispe.~ g pigments to i~llyalL to a polyester thermoplastic composition a granite, fleck-like or speckled surface appearance to an extruded sheet which provides a separate, visibly distinct and identifiable color at numerous sites across the surface of the material wherever the pigment material is visible.
oPotential non-dispersing pigments which are useful provided the aspect ratio is suitable include titanium whiskers and other natural fibers as well as ground thermosetting resin, thermoplastic or rubber m~t~n~l~. When added to a filled polyester mAtPri~l, the resulting decolalive polyester composition typically has chP~ l resistant properties. U.S. patent 5,304,592 to Ghahary 5relates to a simulated mLnelal article which co~ lises a plastic particulate oftherrnoplastic and thermosetting resin material within a therrnoplastic matrix.
It is desired to obtain further enhancements to polyester materials, especially deco-clti~e filled type chemically resistant polyesters, which enhancements include better thermoformability in large parts, greater 20stiffness, better i~ esislance, and higher heat l~si~t~-ce. Hence, it is desirable to provide polyester materials having e~h~nce~ structural ~ro~e,Lies without detracting from the decorative surface and chemical resistant ~lo~lies. Additionally, it is desirable to provide econornically decolaLive and cl~mir~lly resistant polyester n~tPri~lc that exhibit reduced 25shrinkage and warpage with thick sections during molding operations.
U.S. patent 4,737,414 to Hirt et al describes a multilayer composite wherein a layer co~ ising an aromatic polyetherimide is ~ c~rlt to a layer coL~ g an aromalic polyester. A tie layer of a copolyesleIcarbonate is described.

Jullu~lal y of the Invention The compositions of the present invention provide for an economical polyester material having enhanced melt strength and elasticity without s undesirably affecting the desirable decolaLive surface and ch~irAI resistant ~L'~ lies.
According to the ylesent invention, there is provided a therrnoplastic composite comprising an extruded therrnoformable self-supporting sheet having an outer decolaLi~re chemically resistant and renewable filled polyester o layer and an ~ Pnt inner supporting thermoplastic layer for enhancing desirable mechanical yroy~ lies of the composite.
The decolalive outer polyester layer com~,ises a colorant, an il,ol~,ic filler, an effeclive amount of a stabilizer, a W stabilizer, and optionally polycdlL,ol,ate, and/or an impact modifier.
For enhancing the mechanical yroyeiLies of the overall coll~yosile~ the adjacent inner the~ll,o~lastic layer co~l~ylises a heat deformable layer having mechanical y~oye~Lies such as impact resistance and melt strength which desirably exceed these yro~e~ lies as possessed by the outer polyester layer.
Also, there is provided a ~rocess for yrepalillg a deco~ative article COln~liS~ly; extruding a mllltil~yered sheet by feeding at least two diKerent resin CGlllyOSil ;tnr~q to an extruder, extruding said at least two resin coll,yo~ilions into the mllltil~yered self-su~olLing coextruded sheet, and therrnofo"lui~g at least a portion of s~id coextruded sheet into a decorative article wherein at least one exterior surface of the article coll,ylises one resin - 25 and an adjacent layer com~iises the other resin. One resin co~ ises the W O 98/41399 PCT~US98/05108 decorative layer and the other layer comprises the s~ orlillg layer as previously set fort~.
Description of the Plefe~led Embodiments The thermoplastic cGlllyosiLe comprises an extruded therrnoforrnable self-Yu~olLillg sheet having an outer decorative ~ A11y resistant filled polyester layer and an adjacent thermoplastic s,l~o~L layer for enhancing desirable IIlPchAnic~l ~rope~Lies of the composite. Both layers are forrned from extrudable resin compositions. It is co~ lplated that a compatibilizing or adhering layer may be included interrnediate to the decorative layer and the ~uy~OlL layer. It is also contemplated that the support layer may be a o larninate or multilayered structure including a regrind layer of unused or scrap resin mAtPriAl that are desirable to be recycled. It is also conLem~lated another polyester layer may be utilized adjacent the support layer so that the entire exterior of the sheet, both top and boLLol~4 are formed from a decorative polyester type mAtf~riAI
It is also cont~l~lated that the layer imn~PrliAtely ~djAcPnt the outer deco~clLiYe layer be another layer of filled polyester material. Plefelably thissecond polyester layer is of a colored polyester material having a color which is in contrast to the outer deco~dLive layer. By removing a portion of the outerlayer by mP~ ..ic~l or other means, the color of the adjacent layer will be 20 revealed. Hence, a decorative design may be imparted to the sheet material using an A.ijp~P.~ layer which contrasts with the outer layer, _nd removing the outer layer in a ~aLL~
The following ~liecllccion relating the ~ alaLion of a multilayered co~ sile mAl~es rerel~llce to coextrusion of multiple layers using a plurality 25 of extruders. Each layer is desirably formed from a single extruder with multiple layers formed by using a number of extruders col~e~onding to the number of layers desired and a suitable die assembly so as to yield the ~ at~loyliate number of layers.
According to the coextrusion ~focess, a plurality of standard extrusion machines may be ~ e(1 Typically the extruder has a housing having a 5 central opeNng with a helical screw mounted for rotation along an axis interior to a barrel portion. A motor drives the screw through a gear reducer.
At one end of the opening, a hopper is utilized for feeding material to be extruded into the rear portion of the screw. Helical threads mounted on the screw are positioned for moving material from the rear portion of the screw o to a forward portion. As the material or feedstock is conveyed along the screw, the feedstock is heated by frictional forces caused by rotation of the screw. It is also c~ telllplated that an external heating source such as an electrical res~ t heaters may be provided to heat the feedstock.
For forming a mt11til~yered coextruded sheet, feedstock in melted form lS is fed from a re~pe-hve extruder to a die ~csemhly. Coextrusion ~y~lell~s forforming m~ yer film or sheets of thermoplastic materials are generally known, as shown for example in DuBois and Pribble's "Plastics Mold Engineering Handbook", Fifth Edition, 1995, pages 524 to 529. As described, several streams of polymer melt from respective extruders are fed to a die 20 having a feedblock for combining the thermoplastic layers ~ heall~ of a die exp~n.cion ~h~mh~r which is generally of the coathanger-type, also refelred to as "fishtailn-type. From the point of combining the melt streams, the die is used to form the combined melt streams into a sheet where the layers have been spread to make a multilayered product. The thickness of each layer in 25 the final sheet is ~ Gl Lional to the thickness of its particular feed-block.
Other structures provide a die cavity for the reception of a sepalale manifold so that the combining of the layers upon exiting the manifold takes place within the die itself and is close as possible to the entrance to the expansion chamber. The manifold co~ ulises a plurality of slotted, layer distribution passages opening into the eA~al~sion chamber, the passages co~ lising ~ntltll~lly spaced apart openings lying parallel to the slotted die opening.
s The resulting multilayed extruded sheet may be formed into a desired shaped final article by thermofo~ g techni~ues known in the art.
TherrnoLollllillg comprises simultaneously heating and forming the extruded sheet into the desired shape. Once the desired shape has be obtained, the formed article is cooled below its thermoplastic Lelll~e~dture and removed o from the mold. In vacuum molding, the extruded sheet is placed over a concave mold and heated such as by an infra-red heater. Vacuum is applied to draw the extruded sheet into place against the mold cavity. The above may be modified by combining positive air ~ressu,c on top of the extruded sheet with vacuum from the underside to increase the molding force. In rnatched lS or coll~lession molding, matched male and female molds or dies are employed and the extruded sheet is formed between the mechanically co~ ressed molds. Molds are typically made from a metal having high ~herrnAl conductivity such as all~lUnUm. Thermofol~ g methods and tools are described in detail- in DuBois and Pribble's "Plastics Mold Engineering Handbook", Fifth F~ition, 1995, pages 468 to 498.
The outer dec~laL~e chemically resislan~ filled layer is a polyester m~tf~ri~l Polyesle~ j include those comprising structural units of the following for~
O O
o ~ 1 0 C A l C
2s wherein each R1 is independently a divalent aliphatic, alicyclic or aromatichydrocarbon or polyoxyalkylene radical, or mixtures thereof and each A1 W O 98/41399 PCTrUS98/05108 is independently a divalent aliphatic, alicyclic or aromatic radical, or mixtures thereof. Examples of suitable polyeslers containing the StTUCture of the above formula are poly(alkylene dicarboxylates), liquid crystalline polyesters, and polyester copolymers. It is also possible to use a branched polyester in which a branching agent, for example, a glycol having three or more hydroxyl groups or a trifunctional or multifunctional carboxylic acid has been in o~yo~dled~ Furtherrnore, it is sometimes desirable to have various co~lc~ L~alions of acid and hydroxyl end groups on the polyester, depending on the lll*m~te end-use of the composition.
o The Rl radical may be, for example, a C2 l0 alkylene radical, a C6 12 alicyclic radical, a C6 20 aromatic radical or a polyoxyalkylene radical in which the alkylene groups contain about 2-6 and most often 2 or 4 carbon atorns. The A1 radical in the above forrnula is most often p- or m-phenylene, a cycloaliphatic or a rnixture thereof. This class of polyester lS includes the poly(alkylene terephthalates). Such polyesters are known in the art as illustrated by the following patents, which are incoryoldled herein by fefe:~ellce.

2,465,319 2,720,502 2,727,881 2,822,348 3,047,539 3,671,487 3,953,394 4,128,526 ~x~ll~lcs of aroll,alic dicarboxylic acids rey.es~l~led by the di~bo~ylated residue Al are isophthalic or Lelephlllalic acid, 1,2-di(p-ca.~.o,.y~henyl)ethane, 4,4'-dicalbOxydiphenyl ether, 4,4' bisbenzoic acid and les lhe~eof. Acids colllaL. ing fused rings can also be present, such as in 1,4- 1,5- or 2,6- naphth~ne~lir~rboxylic acids. The y,~2fe~.ed dica~l~xylic 2s acids are terephthalic acid, isophthalic acid, naphthalene dica~l.oxylic acid, cyclohexane dicalboxylic acid or mix~res thereof.
The most yi~elled polyesters are poly(ethylene Lel~eyhlhalate) ("PET"), and poly(1,4-butylene terephthalate), ("PBT"), poly(ethylene naphthanoate) .

("PEN"), poly(butylene naphthanoate), ("PBN") and (polypropylene terephthalate) ("PPT"), and mixlule3 thereof.
Also colllelllylated herein are the above polyesters with minor amounts, e.g., from about 0.5 to about 5 yercent by weight, of units derived s from aliphatic acid and/or aliphatic polyols to form copolyeal~ s. The aliphatic polyols include glycols, such as poly(ethylene glycol) or poly(butylene glycol). Such polyesle~s can be made following the teachings of, for example, U.S. Pat. Nos. 2,465,319 and 3,047,539.
The yref~ ed poly(1,4-butylene terephthalate) resin used in this o invention is one obtained by polymerizing a glycol component at least 70 mol %, plefelably at least 80 mol %, of which consists of tetramethylene glycol and an acid or ester co-~lyu-lent at least 70 mol %, ylefe~ably at least 80 mol %, of which consists of terephthalic acid, and polyester-forrning derivatives therefole.
The yref~ed polyesl~ used herein have an i~lLIillaic viscosity of from about 0.4 to about 2.0 dl/g as rne~cllred in a 60:40 phenol/tetrachloroethane u~e or similar solvent at 230-30o C. Preferably the illllillsic viscosity is 1.1to 1.4 dl/ g.
Pre~fdbly, the polyester composition includes a decorative component Typical decG~alive components include colorants in the form of dyes and fillers. One such decorative colorant is ~eS~nhe~l in U.S. patent 5,510,398 to aark et al. A speckled surface is achieved through a non-disyel jing pigment as opposed to a filler because the non-di~pe~ jing pigment does not a~yreciably add to the base color of the resin. Rather, the non-disy~ g pigment provides a separate, visibly distinct and identifiable color at numerous sites across the surface of the material wherever the pigment material is visible. In other words, the speckle is visible in the filled polymer matrix as a distinct region of contrasting color.

CA 022s4973 1998-11-12 W O 98/41399 PCTrUS98/05108 The p~felled polyester composition is a blend with a polycarbonate resin. Polycarbonate resins useful in ~e~aring the blends of the ~resent invention are p~Ffe~ably aromatic polycall~ol,ate resins. Typically these polycarbonates are ~Le~aled by reacting a dihydric phenol with a carbonate 5 pre~u~or, such as phosgene, a haloformate or a carbonate ester. Carbonate polymers may be typified as possessing recurring structural units of the forrnula o Il _o--A O C
wherein A is a divalent aromatic radical of the dihydric phenol o employed in the polymer producing reaction. The dihydric phenols which may be employed to provide such aromatic carbonate polymers are mononuclear or polynuclear aromatic compounds, col~tdil~ing as functional groups two hydroxy radicals, each of which is attached directly to a carbon atom of an aromatic nucleus. Typical dihydric phenols are: 2,2-bis(4-5 hydroxyphenyl) ~lo~.e; hydroquinone; resorcinol; 2,2-bis(4-hydroxyphenyl) E,elltane; 2,4'-(dihydr~,xydiphenyl) methane; bis(2-hydroxyphenyl) methane;
bis(4-hydroxy~henyl) methane; 1,1-bis(4-hydroxyphenyl)-3,3,5-trirnethylcyclohexane; fluorenone bisphenol, 1,1-bis(4-hyd.oxy~henyl) ethane; 3,3-bis(4-hy~o,~y~henyl) pentane; 2,2-dil-y~oxydi~henyl; 2,6-20 dihy~xy~ ht~ on~; bis(4-hydroxydiphenyl)sulfone; bis(3,5-diethyl~
hydroAypllenyl)sulfone; 2,2-bis(3,5-dibromo~-hydroxyphenyl)~ro~,e; 2,2-bis(3,5-dirnethyl 1 hydroxy~henyl)propane; 2,4'-dihydroxydiphenyl sulfone;
5'~hloro-2,4'-dihydroxydiphenyl sulfone; bis-(4-hydroxyphenyl)diphenyl sulfone; 4,4'-dihydroxydiphenyl ether; 4,4'-dihydroxy-3,3'-dichlorodiphenyl 25 ether; 4,4-dihydroxy-2,5-dihydroxydiphenvl ether; and the like.

W O 98/41399 PCT~US98/05108 Other dihydric phenols which are also suitable for use in the dtion of the above polycalbollates are disclosed in U.S. Pat Nos.
2,999,835; 3,038,365; 3,334,154; and 4,131,575.
These aromatic polycarluol-ates can be rnanufactured by known s processes, such as, for exarnple and as mentioned above, by reacting a dihydric phenol with a carbonate precursor, such as phosgene, in accordance with methods set forth in the above-cited literature and in U.S. Pat. No.

4,123,436, or by transesterification processes such as are disclosed in U.S. Pat.
No. 3,153,008, as well as other processes known to those skilled in the art.
It is also possible to employ two or more different dihydric phenols or a copolymer of a dihydric phenol with a glycol or with a hydroxy- or acid-terminated polyester or with a dibasic acid in the event a carbonate copolymer or interpolymer rather than a homopolymer is desired for use in the preparation of the polycarbonate ~l.ixlules of the invention. .Polyarylates 5 and polyester-carbonate resins or their blends can also be employed.
Branched polycall,ol ates are also useful, such as are described in U.S. Pat.
No. 4,001,184. Also, there can be utilized blends of linear polycarbo~ e and a branched polyc~l,onate. Moreover, blends of any of the above materials may be employed in the practice of this invention to provide the aromatic 20 polycall,ol.ate.
In any event, the ylefe~ed aromatic carbonate for use in the practice in the y~sent illvt:nlion is a homopolymer, e.g., a ho~lloyolymer derived from 2,2-bis(~hydro,.yyhenyl)propane (bisphenol-A) and phosgene, commercially available under the trade designation LEXAN Registered TM from General 25 Electric Colllyarly.
The instant polycarl,ol~ate~ are yrefelably high molecular weight aromatic carbonate polymers having an intrinsic viscosity, as ~let~ ;"ed in chloloLollll at 250 C of from about 0.3 to about 1.5 dl/grrl, yrefe~ably from WO 98/41399 PCTrUS98/05l08 about 0.45 to about 1.0 dl/gm. These polycarbonates may be branched or unbranched and generally will have a weight average molecular weight of from about 10,000 to about 200,000, y,e~ldbly from about 20,000 to about 100,000 as measured by gel permeation chromatography.
s The branched polycarl,ollates may be prepared by adding a branching agent during polymerization. These branching agents are well known and may comprise pol~fullclional organic co~ oul-ds containing at least three functional groups which may be hydroxyl, Ca1~OAY1~ ca~l,o~ylic anhydride, haloformyl and mixtures thereof. Specific examples include trimellitic acid, o trimellitic anhydride, trirnellitic trichloride, tris-p-hydroxy phenyl ethane, isatin-bis-phenol,tris-phenol TC (1,3,5-tris((p-hydroxyphenyl)isGylo~yl)benzene),tris-phenol PA (4(4(1,1-bis(p-hy~ o~yl~henyl)-ethyl)alpha~ alpha-dimethyl benzyl)phenol), 4-chlorofo~ yl phthalic anhydride, trimesic acid and benzophenone tetracarboxylic acid.
IS The ~Jiallching agent may be added at a level of about 0.05-2.0 weight y~cellt.
Branching agents and procedures for making branched polycal).ol.att:s are ~1~c~rihe~ in U.S. Letters Pat. Nos. 3,63~,895; 4,001,184; and 4,204,047 which are incol~olaLed by r~felcnce. All types of polycarL,ollate end ~,ro~l~s are conlel~l~lated as being within the scope of the ~lesellt invention.
It is further ~ ed to employ an inorganic filler to the thermoplastic resin to i~llyall A~li*OrlAl beneficial properties such as thPrrnAI stability, increased density, and le,.l~. Inorganic fillers provide a ceramic-like feel to articles th~rmoforn~e~l from resin composition. Pl~f~,.ed inorganic fillers which are employed in the present thermoplastic compositions include: zinc oxide, l~ariulll sulfate, ~irc~,lliuln silicate, shonli-m~ sulfate, as well as s of the above. The yle~Lled form of barium sulfate will have a particle size of 0.1-20 microns. The barium sulfate may be derived from a natural or a SYnL1leliC source.

W O 98/41399 PCT~US98/05108 The molding co~ osilions may include from 20 - 85% by weight, ~.efe~ably 30 - 75% by weight or most ~referably 30 - 45% by weight of total coll~osilion of an inorganic filler colll~o.lent. For certain applications wherea ceramic like product is desired, more than 50%, or more ~refelably 60 - 85%
s by weight of the total composition of filler component should be employed.
The filler material is chosen to enhance the decoralive ~fo~elLies and the renewable properties of the resin sheet. The metal sulfate salts as well as their hydrates are ~vrefel~ed mineral fillers. Plefe,led metal sulfate salts are the Group IA and Group IIA metal sulfates with barium, calcium and magnesium l0 sulfates being prefe~.ed. Barium sulfate which is non-toxic and insoluble in dilute acids is especially ~lefelled. Barium sulfate may be in the form of the naturally OccL~ g balyLes or as synthetically derived baliulll sulfate using well known synthetic techniques. The particle size may vary from 0.5 to 50 microns, ~reLe~dbly from 1 to 15 microns and most pl~felably 8 rnicrons.
The coln~osilion desirably contains impact modifiers such as a rubbery impact modifier. r~fe~dbly such impact modifiers are utilized in an amount less than about 30, and plefelably less than about 20 pcrcell~, more ~leferdbly less than about 15 ~ere~llt by weight based on the total weight of the composition.
The l,lefe.led th~rrnofo~ll~lg additives for thermofoillii~.g have a linear or radial (branched) A-B-A block structure. They include styrene-but~ ne-styrene (SBS) and styrene-isoprene-styrene (SIS). A diblock polymer of the type styrene-ethylene/propylene (SEP) is also included. The most ~reLelled thermofoll-~g additive is of the A-~A block structure of the type styrene-ethylene/butylene styrene (S-EB-S).
The filled polyester molding composition includes a polyester resin, an inorgaruc filler material, a polycarbonate resin; and an eLLe.live amount of a styrenic modifier which may include random, block, and radial block copolymers. A particularly useful class of modifiers conl~lises the AB
(diblock) and ABA (triblock) copolymers alkenylaromatic col~ounds, especially those co-,l~,ising styrene blocks. The conjugated diene blocks may be ~lls~ dled~ partially or entirely hydrogenated, whereupon they may be 5 re~ie3ented as ethylene-propylene blocks or the like and have ~ulo~e~lies similar to those of olefin block copolymers. Examples of triblock copolymers of this type are poly~ly,e.le-polybutadiene-polyslyl~,le (SBS), hydrogenated polysly~t:ne-polybutadiene-polystyrene (SEBS), poly~ly.~l,e-polyisoprene-poly~lyLt:lle (SIS), poly (a-methylstyrene)-polybutadiene-poly(a-o methylstyrene) and poly(a-methylstyrene)-polyisoprene-poly(a-methylstyrene). ParticuIarly t,re~ed triblock copolymers are available commercially as CARIFLEZ~), lCraton D~, and KRATON G~ from Shell.
Typical impact modifiers are derived from one or more monomers selected from the group consisting of olefins, vinyl aromatic monomers, s acrylic and alkylacrylic acids and their ester deliv~tives as well as conjugated dienes. Impact modifiers include the rubbery high-molecular weight materials including natural and synthetic polymeric materials showing elasticity at room lel~ dl~lle. They include both homopolymers and copolymers, including random, block, radial block, graft and core-shell 20 copolymers as well as combinations thereof. Suitable modifiers include core-shell polymers built up from a rubber-like core on which one or more shells have been grafted. The core typically consists substantially of an acrylate rubber or a butadiene rubber. One or more shells typically are grafted on the core. The shell ~refe~ably comprises a vinylaromatic colll~oulld and/or a 25 vinylcyanide and/or an alkyl(meth)acrylate. The core and/or the shell(s) often colll~lise multi-functional compounds which may act as a cross-linking agent and/or as a grafting agent. These polvmers are usually prepared in several stages.

CA 022~4973 1998-11-12 Olefin-containing copolymers such as olefin acrylates and olefin diene terpolymers can also be used as irnpact modifiers in the present compositions.
An example of an olefin acrylate copolymer impact modifier is ethylene ethylacrylate. Other higher olefin monomers can be employed in copolymers 5 with alkyl acrylates, for example, propylene and n-butyl acrylate. The olefin diene terpolymers are well known in the art and generally fall into the EPDM
(ethylene propylene diene) farnily of terpolymers. Polyolefins such as polyethylene, polyethylene copolymers with alpha olefins are also of use in these compositions. Polyolefin copolymers with gylcidyl acrylates or o methacrylates may be especially effective in the impact modification of polyester containing blends.
Styrene-cGnldi~ g polymers can also be used as impact modifiers.
Examples of such polymers are acrylonitrile-butadiene-styrene (ABS), acrylonitrile-butadiene-alpha-methylstyrene, styrene-b lt~C~iene, styrene butadiene styrene (SBS), styrene ethylene butylene styrene (SEBS), methacrylate-butadiene-styrene (MBS), and other high impact styrene-containing polymers.
Impact modifiers are typically based on a high molecular weight styrene-diene rubber. A pre~ed class of rubber materials are copolymers, 20 including random, block and graft copolymers of vinyl aromatic compounds and conitlg~t~l dienes. Exemplary of these materials there may be given hydro~ .1, partially hydrogenated, or non-hydrogenated block copolymers of the A-B-A and A-B type wherein A is poly~lyl~ e and B is an elastomeric diene, e.g. polybutadiene, polyisoprene, radial teleblock 25 copolymer of styrene and a Y conjugated diene, acrylic resin modified styrene-butadiene resins and the like; and graft copolymers obtained by graft-copolym~n~hon of a monomer or monomer mix containing a styrenic co.11pol,nd as the main co~ onent to a rubber-like polymer. The rubber-like CA 02254973 1998-ll-12 WO 98/41399 PCT~US98/05108 polymer used in the graft copolymer are as already described herein including polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, ethylene-propylene copolymer, ethylene butylene copolymer, polyacrylate and the like. The styrenic co~ ou~-ds includes styrene, methylstyrene, dimethylstyrene, isopropylstyrene, a-methylstyrene, ethylvinyltoluene and the like.
Procedures for the preparation of these polymers are found in U.S.
Patent Nos. 4,196,116; 3,299,174 and 3,333,024, all of which are incol~oi~lted by ref~ e.
o An effective arnount of a block copolymer of the A-B-A may be utilized as impact modifier. In accordance with the principles of the ~esel.t illvel~Lion, the A-B-A type ingredient is present an amount sufficient for enhancing the thermo-formability of articles produced from the resin. A is a polymerized mono-alkenyl aromatic hydrocarbon block and B is polymerized lS conJugated diene hydroca.bon block.
In the above type, blocks A typically consliL.Il;.,g 3-50 weight percent of the copolymer and the unsaturation of block B having been reduced by hydrogenation. The filled polyester molding composition of the present il~v~llLion co~ ises from 5~0 parts by weight, and ~ref~lably 10-30 parts by weight of the block copolymer.
With res~ecl to the hydrogenated block copolymers of the A-B-A type, they are made by means known in the art and they are commercially available.
These materials are described in U.S. Pat. No. 3,421,323 to Jones, which is hereby incor~o.aLed by refelence.
Prior to hydrogenation, the end blocks of these copolymers comprise homopolymers or copolymers t,lefe~ably prepared from alkenyl aromatic hydrocalbul~s and particularly vinyl aromatic hydlocalbons wherein the aromatic moiety may be either monocyclic or polycyclic. Typical monomers include styrene, alpha methyl styrene, vinyl xylene, ethyl vinyl xylene, vinyl naphthalene and the like or ~ Lul~es thereof. The end blocks may be the same or di~elel~t. The center block may be derived from, for example, polyisoprene or polybutadiene.
The ratio of the copolymers and the average molecular weights can vary broadly although the molecular weight of center block should be grealel than that of the combined terminal blocks. Typically, terminal blocks A have average molecular weights of 4,000-115,000 and center block B e.g., a 0 polybutadiene block with an average molecular weight of 20,000450,000. Still more ~refer.tbly, the terminal blocks have average molecular weights of 8,000-60,000 while the polybutadiene polymer blocks has an average molecular weight between 50,000 and 300,000. The terminal blocks may colllylise 2-50%
by weight, or more ~reLelably, 5-30% by weight of the total block polymer.
The ~refel~ed copolymers will be those formed from a copolymer having a polybllt~ Prle center block wherein 35-55%, or more yrefelably~ 40-50% of the butadiene carbon atoms are vinyl side chains.
Block copolymers such as Kraton G-GXT-0650, Kraton G-GXT-0772 and Kraton G-GXT-0782 are available from Shell Chemical Company, Polymers Division.
Block copolmers of the A-~A type may also be considered with re~e.L to the formula A'-B'-A' block copolymers.
The ratio of the co-monomers may vary broadly. Typically, the the molecular weight center block is greater than that of the combined terminal 2s blocks. Preferably, with the above limitation, the molecular weight of the terminal Wocks each will range from about 2000 to about 100,000 while that of the center block will range from about 25,000 to about 1,000,000.

WO 98/41399 PCT/US98/~5108 The impact modifier is desirable present in an amount from 0 to 40 percent by weight, ~refeldble from 4 to 15 ~ereenl, for deep drawing sheets, a higher level on the order from 20 to 40 percent is ~.e~ d.
In the thermoplastic compositions which cGllla~ a polyester and a 5 polycarbonate resin, it is plefelable to use a stabilizer material. Typically,such stabilizers are used at a level of 0.01-10 weight percent and ~lefe~ably ata level of from 0.05-2 weight ~e~cent.
The pre~ ed stabilizers include an effective amount of an acidic phosphate salt; an acid, allcyl, aryl or mixed phosphite having at least one o hydrogen or alkyl group; a Group IB or Group IIB metal phosphate salt; a phosphorous oxo acid, a metal acid pyrophosphate or a ll~lure thereof. The suitability of a particular coll-~oul~d for use as a stabilizer and the determination of how much is to be used as a stabilizer rnay be readily deL~ lulled by preparing a lni~Lule of the polyester component, the 5 polycarbonate and the filler with and without the ~alLi-ular compound and determining the effect on melt viscosity or color stability or the formation of inlelpolymer. The acidic phosphate salts include sodium dihydrogen phosphate, mono zinc phosphate, potassium hydrogen phosphate, calcium hydrogen phosphate and the like. The phosphites may be of the forrnula:
R6o-?-oR7 oR8 where R6, R7 and R8 are independently c~lecte-l from the group consisting of hydrogen, alkyl and aryl with the proviso that at least one of R6,R7 and R8 is hydrogen or aL~cyl.
The phosphate salts of a Group IB or Group IIB metal include zinc phosphate, copper phosphate and the like. The phosphorous oxo acids include phosphorous acid, phosphoric acid, polyphosphoric acid or hypophosphorous acid.

The polyacid pyrophosphates of the formula:
MZx Hy Pn ~3n+1 wherein M is a metal, x is a number ranging from 1 to 12 and y is a number ranging 1 to 12, n is a number from 2 to 10, z is a number from 1 to 5 and the sum of (xz)+y is equal to n+2.
These compounds include Na3HP2O7; K2H2P2O7; Na4P2O7;
KNaH2P207 and Na2H2P2O7. The particle size of the polyacid pyrophosphate should be less than 75 microns, ~lefe~dbly less than 50 microns and most yrefelably less than 20 microns.
o The ~refe,red polyester layer comprises a decorative component, polycarbonate, an organic filler, a reinforcing material, and a stabilizer. The polyester material ~referdbly comtJ~ises EnduranTM 7322 available from the GE Plastics coml.onent of General Electric Company is a plefelled polyester resin material for the outer layer.
IS A ~efelled composition includes the following: polyester from about 10 to about 40 yel'cellt by weight, preferably the polyester comprising polybutylene terephthalate in an amount from about 7 to about 25 ~elcel.t and polyethylene terephthalate from about 3 to about 10 percent, aromatic polycarbo,lale from about 10 to about 25 percent, stabilizer from about 0.01 to about 10 percent, impact modifier from 4 to about 15 percent, barium sulfate from about 30 to about 40 percent, with pigment or dyes being present in an e~e~Lve amount to generate the desired surface effect and when combined with ~ itinnal ingredients being present in an amount less than about 5 percent.
An adjacent thermoplastic support layer co~ ises a heat deformable material having mechanical pn~p~lies such as impact resistance and melt strength which desirably exceed such properties of the decorative polyester layer so as to enhance the mechanical properties of the composite. Suitable CA 022s4973 1998-ll-12 W O 98/41399 PCT~US98/05108 thermoplastiC organic polymers for the inner layer includes acrylonitrile-butadiene-styrene (ABS), polycarbonate, polycarbonate/ ABS blend, a copolycarbonate-polyester, acrylic-styrene-acrylonitrile (ASA), acrylonitrile-(ethylene-poly~o~ylene diamine modified)-styrene (AES), phenylene ether resins, blends of polyphenylene ether/polyamide (NORYL GIX~) from General Electric Company), blends of polycarbonate/polybutylene terephthalate and impact modifier (XENOY~ resin from GeneraI Electric Company) blends of polycarbonate/PET/PBT, polyarnides, phenylene sulfide resins, ), poly(vinyl chloride) PVC, polymethylmethacrylate (PMMA), and High-impact Poly~Ly~ e (HIPS
A plef~lled composition for the support layer comprises an ABS type polymer. In general, ABS type polymers contain two or more polymeric parts of different co~ osilions which are bonded chemically. The polymer is ~refeldbly E~re~ared by polymerizing a conjugated diene, such as butadiene lS or a conjugated diene with a monomer copolymerizable therewith, such as styrene, to provide a polymeric backbone. After formation of the backbone, at least one grafting monomer, and preferably two, are polymerized in the presence of the prepolymerized backbone to obtain the graft polymer. These resins are prepared by methods well known in the art.
The backbone polymer, as mentioned, is ~re~eldbly a conjl-~te~ diene polymer such as polybutadiene, polyisoprene, or a copolymer, such as bu~tli~ne-styrene, butadiene-acrylonitrile, or the like. Examples of dienes that may be used are butadiene, isoprene, 1,3-hepta-diene, methyl-1,3-pe~t~ P, 2,3-dimethyl-1,3-butadiene, ~-ethyl-1,3-pentadiene; 1,3- and 2,~
2s h~x~c1ierles, chloro and bromo substituted butadienes such as dichlorobutadiene, bromobutadiene, debromobutadiene, mixtures thereof, and the like. A p~e~"ed conjugated diene is butadiene.

CA 022~4973 1998-11-12 One monomer or group of monomers that may be polymerized in the presence of the prepolymerized backbone are monovinylaromatic hydrocarbons. Examples of the monovinylaromatic compounds and alkyl-, cycloalkyl-, aryl-, alkaryl-, arallcyl-, alkoxy-, aryloxy-, and other substituted 5 vinylaromatic coll.pounds include styrene, 3-methylstyrene; 3,5-diethylstyrene, 4-n-propylstyrene, alpha -methylstyrene, alpha -methyl vinyltoluene, alpha -chlorostyrene, alpha -bromostyrene, dichlorostyrene, dibromostyrene, tetra-chlorostyrene, mixtures thereof, and the like. The ~lefelled monovinylaromatic hydrocarbons used are styrene and/or alpha-lo methylstyrene.
A second group of monomers that may be polymerized in the presenceof the prepolymerized backbone are acrylic monomers such as acrylonitrile, subsliluled acrylonitrile and/or acrylic acid esters, exemplified by acrylonitrile, and alkyl acrylates such as methyl methacrylate. Examples of IS such monomers include acrylonitrile, ethacrylonitrile, methacrylonitrile, alpha -chloroacrylonitrile, beta -chloroacrylonitrile, alpha -bromoacrylonitrile, and beta -bromoacrylonitrile, methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, propyl acrylate, isoyn~ l acrylate, and mixl~lres thereof. The p~ led acrylic monomer is acrylonitrile and the E,reftlled 20 acrylic acid esters are ethyl acrylate and methyl methacrylate.
In the preparation of the graft polymer, the conjl-g~te-l diolefin polymer or copolymer exemplified by a 1,3-butA~ e polymer or copolyrner co~ lises about 50% by weight of the total graft polymer composition. The monomers polymerized in the presence of the backbone, exemplified by 25 styrene and acrylonitrile, com~lise from about 40 to about 95% by weight of the total graft polymer col~,~osilion.
The second group of grafting monomers, exemplified by acrylonitrile, ethyl acrylate or methyl methacrylate, of the graft polymer composition, W O 98/41399 PCT~US98/05108 preferably co...l,lise from about 10% to about 40% by weight of the total graft copolymer composition. The monovinyiaromatic hydrocarbon exemplified by styrene comprise from about 30 to about 70% by weight of the total graft polymer composition.
5In preparing the polymer, it is normal to have a certain percentage of the polymerizing monomers that are grafted on the backbone combine with each other and occur as free copolymer. If styrene is utilized as one of the grafting monomers and acrylonitrile as the second grafting monomer, a certain por*on of the composition will copolymerize as free styrene-oacrylonitrile copolymer. In the case where alpha -methylstyrene (or other monomer) is sul)sli~ d for the styrene in the composition used in preparing the graft polymer, a certain percentage of the composition may be an alpha -methylstyrene-acrylonitrile copolymer. Also, there are occasions where a copolymer, such as alpha -methylstyrene-acrylonitrile, is added to the graft 5polymer copolymer blend. When the graft as polymer-copolymer blend is referred to herein, it is meant optionally to include at least one copolymer blended with the graft polymer composition and which may contain up to 90% of free copolymer.
Optionally, the elastomeric backbone may be an acrylate rubber, such 20as one based on n-butyl acrylate, ethylacrylate, 2-ethylhexylacrylate, and thelike. A~l~li*on~lly, minor amounts of a diene may be copolymerized in the acrylate rubber backbone to yield improved grafting with the matrix polymer.
The pl~fel~ed ABS material for the support layer comprises Cycolac~
GPX3800 and Cycolac~) I~A resin available from the GE Plastics colnl,olLent 25of General Electric Company.
Additional material for the support layer include polycarbonate and polycarbonate blends. The polycarbonate is as before described with Lexan(~) resin available from GE Plastics component of General Electric Company a , CA 022~4973 1998-11-12 ~refelled polycarbonate. Resin blends of polycarbonate may also be used.
P~èfe~led polycarbonate resin blends include Xenoy(~1731, a polycarbonate poly (butylene terphthalate) blend, Cycoloy~MC8002 and MC8100 blends of polycarbonate and ABS.
Typical polyphenylene ether resin is a poly(2,6-dimethyl-1,4-phenylene)ether resin having an intrinsic viscosity of from about 0.3 dl/g to about 0.60 dl/g in chloroform. The polyphenylene ether resins useful herein are well known in the art and may be prepared from a number of catalytic and non-catalytic processes from corresponding phenols or reactive derivates o thereof. Examples of polyphenylene ethers and methods for their production are disclosed in U.S. Pat. Nos. 3,306,874; 3,306,875; 3,257,357 and 3,257,358, all incorporated herein by refe~e~ce.
Typical polyamides suitable for the present invention may be obtained by polymerizing a monoamino monocarboxylic acid or a lactam thereof having at least 2 carbon atoms between the amino and carboxylic acid group;
or by polyrnPri~ing substantially equimolar l,ro~orlions of a diamine which contains at least 2 carbon atoms between the amino ~,lOU~/S and a dicarboxylic acid; or by polymerizing a monoaminocarboxylic acid or a lactam thereof as defined above together with substantially equimolecular ~ro~olLions of a diamine and a dica~,o~-ylic acid. The dicarboxylic acid may be used in the form of a functional delivaLive thereof, for example an ester.
Multilayer structures of ENDURAN~ 73~ resin with other resins offer lower cost alternatives to monolayer ENDURAN~) 73~ resin while maintaining the surface appearance of a ENDURAN(8) 73~ resin layer by substituting a portion of the ENDURAN(~)7322 resin layer with lower cost resins. Performance ~ro~ ies such as stiffness, heat resistance, impact resistance and/or flamrnability in the structures are i~ oved by inc~ lating materials which enhance these yLo~e~ lies relative to the CA 02254973 1998-ll-12 W O 98/41399 PCTrUS98/05108 performance of monolayer ENDURAN~) 7322 resin- Processing advantages in thermoforming are also realized by inco~)o~ating materials with greater melt strength than the monolayer structure so that larger parts may be thermofo~ e~
Multilayer structures of ENDURAN~) 7322 can be combined with various other resins to create systems with reduced cost and/or improved o~ll,ance. These other resins include ABS (CYCOLAC(~ GPX3800 resin, CYCOLAC~) LSA resin), PC/PBT blends (XENOY~ resin), polycarbonate (LEXAN~) resin), PC/ABS blends (CYCOLOY~ MC8002 resin, CYCOLOY(~
o MC8100 resin), PPO~) resin based blends (NORYL~ resin), poly(vinyl chloride) PVC, and High-impact Polystyrene (HIPS). These resins may also contain reinforcing fillers (such as glass fibers) which increase stiffness of the structure.
These structures may be produced by coextrusion and may consist of one or more different materials in addition to the ENDURAN~ 73Z layer.
Layers may include regrind material. Sheet produced by coextrusion may be then thermoformed to fabricate parts. Sheet or fabricated parts maintain the surface qll~lities (a~earal~ce, feel, etc.) of monolayer ENDURAN~ 73Z
products and may also be used with special color effects used with ENDURAN~ 7322 monolayer sheet.
Thermofo~ning of the sheet is perforrned by placing the sheet over a concave mold and heated such as by an infra-red heater. Vacuum is applied to draw the extruded sheet into place against the mold cavity. Combinations of ENDURAN(~ 7322 with CYCOLAC~ GPX3800, CYCOLAC~ LSA, and CYCOLOY(~ MC8002 have been co-extruded and thermoformed on a 12" x 12" tool with 1" depth. All three combinations have produced good ~uality sheet with good adhesion and material compatibility. Thermoformed parts W O 98/41399 PCT~US98/05108 retained adhesion of layers and surface quality. Other combinations are being extruded and thermoformed.
Multilayer structures can be used either as surfacing materials (for counl~lLo~s or wall coverings) in the form of coextruded sheet, or in any s thermofol.~ g application involving ENDURAN~) 7322 resin such as sinks or tubs.
Pl~f~lled thickness for the outer decorative layer is from about 0.002 inch (2 mils) to about .250 inch (0.250 mils) with ~lefe~ed thicknesses of the backing thermoplastic layer being from about 0.050 inch (50 mils) to about .500 inch (500 rnils).
rlefelled multilayered structures include the following as set forth below:
EnduranTM resin/Cycolac(g) resin for thermofollllillg sinks and other articles.
lS A two layered structure having a total thickness of 200 to 400 mils, ~vre~e~ably 300 mils, with the outer cap layer being 15 to 40 percent of the total thi-~knP~s EnduranTM resin/Cycolac~) resin for surfacing applications such as counters and wall.
A two layered structure having a total thickness of 90 to 125 mils, with the outer cap layer being 15 to 30 percent of the total thickness.
~nrlllranTM resin/ EnduranTM resin for decolaLive surfacing applications such as counlels and wall where a pattern is developed by removal of a portion of the outer layer to expose an A~jAcent layer.
A two layered structure having a total thickness of 90 to 125 mils, with the outer cap layer being 15 to 30 percent of the total thickness.
A two layer structure comprises En~iuranTM resin/ Cycolact~) resin and regrind lllix.L~ile. The outer cap layer is al~out 33% of the total thickness. The -total thickness is 90 rnils. The Cycolac(l~) resin and regrind lllixlure contains 50% by weight regrind.
A three layer structure coln~lises is EnduranTM resin/Cycolac~) resin and regrind mL~clule/cycolac(~) resin. The outer cap layer is about 33% of the 5 total thickness. The total thickness is 90 mils. The Cycolac(g~ resin and regrind mixture conlains 50% by weight regrind. The boll~ layer of Cycolac~) resin is 33% of the total thickness. As referred to in these examples,the regrind layer comprises polyester resin and acrylonitrile-butadiene-styrene resin which remain after processing in the forrn of scrap and excess 10 material. The scrap material is ground and incorporated into the multilayered structure as a separate layer or as part of an acrylonitrile-butadiene-styrene resin layer.
A most ~ef~lled two layer structure co~ lises a co-extruded layer of EnduranTM 7322 resin, Table 1, adjacent a layer of Cycolac(~) 29344A resin, Table 2. EnduranTM resin and Cycolac(~) resin are available from the GE
Plastics col~l~Gnent of General Electric Company.

Table 1 - EnduranTM resin wt% of ingredient based on total wt%
Valox~ 315 resin - poly(butylene terephthalate) - General Electric 17.45 Company Lexan(~ 131 resin - polycarbonate - General Electric Company 27.25 poly(ethylene terephthalate) 9.8 Kraton G 1651 SEBS a slly~n-ethylene butylene-styrene block 7.5 copolymer - Shell Chemical Co.
BaS04 37.0 PETS - tetrakis(methylene(3,5-di-tert-butyl-4- 0.2 hydroxyhydrocinnamate))methane TINWIN 234 - W absorber (Tinuvin 234, a benzotriazole 0.3 PEP-Q - tetrakis(2,4-di-tert-butylphenyl)4,4'- 0.3 biphenylenediphosphonite (Sar~lostAb P-EPZ phosphonite Irgafos 168 0.1 MZP Mono zinc phosphate dihydrate (Zn(H2PO4)2H20) 0.1 Table 2 - Cycolac~ resin wt% of ingredient based on total wt%
360 HRG - High Rubber Graft ABS 60 570 SAN - styrene-acrylonitrile 40 Pluronic F-88 - 0.2 wingstay~) L antioxidant stabilizer 0.15 Ultranox~ 626 stabilizer - GE Specialty Chemicals 0.2 silicone fluid 0.10 Santicizer 0.40 CA 022~4973 1998-11-12 The desired thickness of the co-extruded sheet is somewhat dependent upon the use of the sheet. Generally, an overall thickness of from 0.02 to 0.50 inch is ~e~ ed with the thickness of the Enduran resin layer being from about 5 to about 85 percent of the total thickness. Some of the l,refelled thickness fors different type of uses are set forth in the Table 3.
Table 3 - Thickness of Enduran resin/Cycolac resin co-extruded layers Total Sheet Thickness % Enduran Shower Wall Surrounds 0.065 20%
Kitchen/bathroom Counters 0.090 40%
Shower Trays o.~o 20%
Lavatory Tops 0.210 20%
Standard size Bathtubs 0.250 30%
Large Jacuzzi Bathtubs 0.285 30%
For a co-extruded two layer sneet, it is highly desirable that the layers be co~ alible so that the layers adhere. It is desirable to avoid ingredients inone layer that might react with the ingredients in the other layer. The above o layers are compatible and are characterized by the absence of reactive materials such as some metal oxides such as magnesium oxide.
To achieve sound damping, it is contemplated that a foam layer may be adjacent the su~uil or inner layer. Typically, the foam layer has a 10 to 50% density reduction for lower cost, weight reduction and sound damping.
IS The foam may be foamed in place. See U.S. 5,486,407 to Noell et. al. It is also contemplated that the inner support layer may be adhered to a cellulosic based material such as a particleboard, fiberboard, chipboard or plywood. It is also contemplated that abrasive resistant coatings such as described in U.S.
5,4~6,767 may be utilized in conjunction with the present invention.
Thermoforming methods may be utilized as set forth in U.S. 5,601,679 to Mulcahy et al. A co-extruded sheet may be vacuum formed. Typically, the vacuum former and surrounding metal framework are preheated to minimize chill of the sheet. The sheet is placed on a vacuum box and mounted on the ~oLl~ side of the former or platten. Clamp frames are activated for mechanically holding the sheet in place. A suitable heat shield, such a 5 aluminum foil, may be utilized for avoiding heating the surface at selected locations such as other than a sink portion. The sheet is then exposed to the thermo-forrning ovens. Top and bottom heaters may be used. During heating, the sheet begins to sag. Once the sheet reaches its proper forming temperature, the assembly is shuttled to a vacuum forming box where sink is o vacuum formed in a box. The box has a plurality openings in a mold form for drawing the sheet into mold during the forming operation. After cooling, the resulting therrnoformed sheet is removed.
The following specific examples illustrate the present invention. The Examples set forth in Table 4 are for comparison purposes, with 5 Formulations 4 and 6 illustrating results employing the ~lefelled rheology modifiers of the pl~sent invention.

ADDITIVES 1 Z 3 4 5 6 .7 8 : lEOM 007 . Ø0 ~ 0 C~ 30 Acr~lic Impact Mod. ~.5.0 0 V.B_-EXL 3n9 ~ 15.0 _~ ADER-'o yolefin 0 0 ~ .0 ~ ~
'CratonG:6 1 1 0 0 ~5.0,.5 . Craton G:6_2 0 7.5 ~el CAl 5611 ~ 0 ' ~ .5.0 0 neL C~ P 5219 ~- 0 f 7-5 PC .~ ar ~ .3 ~ 7.1 ~7.1 n9 3 7.1~7.1 ~7.1 ~- .7 PB' 1 , ~ear :,~ .8 :,7.0 37.0 5.8 .,7.0 37.0 37.0 ., .9 Sta~I~izer. ackage ~.(3 .9 0.0 t.9 ~.9 .9 ~.9 1 9 TEST RESULTS
Melt Elasticity (% ElollgaLiOIl~ >555 >555 >555 ~5;5>555 >555 ~555 >555 CA 022S4973 l998-ll-l2 Table 4 contains comparative studies of various rheology modifiers in unfilled systems. Regardless of the modifier used, the melt elongation of the result,ing formulation is well above 555%. Hence, these sy~ell s do not dif~erellliate between the rheology modifiers used.
s Table 5 is directed to the comparison of rheology modifers in filled systems.

ADD~n~ 1 _ 3 4 5 6 7 8 9 10 11 ~EOMu07 ~ l~ ~5.0 0.0 750 0 00 -50 ~B -E~;3n 1 I- " 0 7 5 0 0 .~ ror C16_ 5 ~ " ~ ~ .5.0 _0.0 , L ne~Ar 1 0.56 .8 . .46 .46 .46 .46 .56 .56 .36 .46 ~.56 , CA ~ 131 Linear PC ~ I , .2 ~ l o CBr~AnchedTMTC 7.2 '~ ~3.4 ~.4 43.4 ~3.4 40.9 ~0.9 45.9 ~3.4 20.92 Bas~d , , , A _ "
V~ OX 315 PBT 7. 7. 5.: .5. S. 5.:. 3. ~ 3. 6 7 5: 3 Ba C~, X7. 7. .,7. '7.~ 7. '~7. 7. 7. 7.0 7. '7.
JtAqLi".. Paclca~e .0 0 .0 .0 .0 0 0 .0 ,05 0 0 TESI RESULTS
Melt Eiastici~ (% 334 375 170 133 127 99 94 150 280 309 270 .Ior~ oll) ~ri~nalT~ckn~s (inch) 0.09 0.09 0.09 0-09 0.09 0.09 009 0.09 0.09 0 09 0 09 art Thickness 0.02 0.02 0.01 0.01 0.01 0.01 0.00 0.00 0.01 0.03(AfterTh~ v~u~ ) 3 6 3 1 1 0 6 5 6 3 0 aearly, the melt elongation drops substantially when moving from unfilled to filled ~yslel~s. Formulations 1, 2, 9,10,11 have the highest melt elongation and all of them are modified with Kraton G1651. To those skilled in the art, the rheology modification of unfilled PC/P8T for enhanced blow molding and/or thermofol~ lg is achieved by using core shell modifiers in single phase or dual phase modification. In the ba~ sulfate filled formulations delineated above, formulations 3 through 8 have the lowest melt elongation, despite the fact that core shell modifiers (HEOM, MBS) are being used. Another key test result of this studv is the vertical wall thickness afterthermoro~ g. Vertical walls in thermotormed part are the most susceptible CA 02254973 l998-ll-l2 W O 98/41399 PCTrUS98/05108 to thinning. Part llu~uung is an important measure of material distribution throughout a given part- Again, formulations 3 through 8 have the lowest thickness retention, while those with Kraton G1651 have the highest.
Consequently, taking into account melt elongation and vertical walI thickness, 5 Kraton G1651 conldilling formulations oul~e,~lll. those containing HEOM
and/or MBS. In Table 5, the influence of high molecular weight acrylic polymer is A~sP~se~ According to Ref. 11, these additives improve the melt strength of unfilled PB/PBT blends.

ADDllTVES 1 2 3 4 _ _ 7 PC ranc.~ed . MTC 3.43 0 1~ ,0.92 PC ~r~l~ Ied L694~ THPE 23.43 l l 0.92 LF~AN 31- nearPC ' .~3.43 "~.92 22.~ 2 K4 O Acrylic .mp. Mod. ~ .O( ~ O .OO
PE Lir e .- r ~7=0.56 .4O ,4n ',4~ .5n ~.1 ,5.7 VA' O~I ~ .5 Linear PBT . . 6 . 6 .~-6 ' .~7 -.~7 -,~ 3 J,-7 Kraton ~ 51 ' . ', . . , ~ , . . . . .
BaSQ4 ~ ' 3"' 3' Stab:~izer Package :.O :.O .O :.O :.O :.O :.O
TEST RESULTS
.. ~lelt El sicity (% Fl.~ ) 4~ )7 809 ~2~ ~79 ~53 ''99 .'art Or ~nal Tl-i~ .. s (inch) . 9 . 19 .09 .O~ .~ 9 .09 .O9 ~artTh. ~ . 80 . 29 ~.038 .0 6 . 15 .0~1 .011 (After T~

The ~ *Qn of the high molecular weight acrylic polymer clearly ~m~o~es the melt elongation as in formulations 4 through 7 compared to formulation 3. However, they do have a deleterious effect on thickness l~lel~liul.; thus, are detrimental to the thermoforming and/or blowmolding of filled PC/PBT blends. The ~refelled compositions have a melt elasticity as %
elongation of greater than about 300.

Table 7 ADDll~VES 1 2 3 4 5 6 7 LEXAN131 LinearPC 23.2 23.2 23.2 23.2 23.2 ~3.2 23.2 VALOX 315 Linear PBT 15.25 15.25 15.25 15.25 15.25 15.25 15.25 PEI Linear IV-0.56 8.50 8.50 8.50 8.50 8.50 8.50 8.50 BaSO4 37 0 37 0 37 0 37 0 37 0 37 0 37 0 Stabilizer Package 1.05 1.05 1.05 1.05 1.05 1.05 1.05 Kraton G1651 (SEBS, High MW) 15.0 Vector 2518 (SBS, Med MW) 15.0 Vector 8508D (SBS, Low MW) 15.0 Kraton G1702 (SEP, High MW) 15.0 Kraton D1102 (SBS, MedLow MW) 15.0 Kraton D1118 (SBS, Med MW) 15.0 Kraton D1184 (SBS, High MW, radial) 15.0 TESI RESULTS

Melt Elasticity (% F~ e,o~ 555 >555 183 ~555 262 214 >555 Un.~Gt.l.ed Izod impact (ft-lb/in) 43 16 14 35 17 17 31 Biaxial impact (ft-lb) 15.7 7.3 6.7 7.1 4.1 6.8 8.6 In Table 7, it is shown that A-B-A type impact modifiers desirable have a high m-llec~ r weight in order to provide a high melt elasticity. In addition, the type of rubbery block affects the impact of the final product, s which is also ~npo~Lallt to its function as a useful thermoformed article.
Although those skilled in the art have relied on branched polymers tc~ystalline and/or arnorphous)- to improve thermoformability and blowmoldability, ~at assertion is not universal in the filled ~y~tt:ms we are evaluating. Formulations 1 and 2 contain branched polycarlJol,ate; however, their melt elongation is lower than that of a formulation which contains a linear but high molecular weight polycarbonate. Moreclver, the thickness retention of vertical walls of thermoformed parts containing branched polycarbonate is not as good as the one with linear high molecular weight s polycarbonate. We would rather advance the dual concept of high molecular weight and branched as being beneficial to thermofo~ g and/or blowmolding.

Claims (18)

What is claimed is:

1. A thermoplastic composite comprising an extruded thermoformable self-supporting sheet having an outer decorative chemically resistant and renewable filled polyester layer and an adjacent inner supporting thermoplastic layer for enhancing desirable mechanical properties of the composite.

2. A thermoplastic composite according to claim 1 wherein said decorative outer polyester layer comprises a colorant, an inorganic filler, an effective amount of a stabilizer, and optionally polycarbonate, and an impact modifier.

3. A thermoplastic composite according to claim 2 wherein the adjacent inner thermoplastic layer comprises a heat deformable layer having mechanical properties such as impact resistance and melt strength which desirably exceed these properties as possessed by the outer polyester layer.

4. A thermoplastic composite according to claim 3 wherein the adjacent inner thermoplastic layer comprises acrylonitrile-butadiene-styrene, polycarbonate, polycarbonate/ acrylonitrile-butadiene-styrene blend, copolycarbonate-polyester, acrylic-styrene-acrylonitrile, acrylonitrile-(ethylene-polypylene diamine modified)-styrene, phenylene ether resins, blends of polyphenylene ether/polyamide, blends of polycarbonate/polybutylene terephthalate and impact modifier, blends of polycarbonate/PET/PBT, polyamides, phenylene sulfide resins, poly(vinyl chloride), polymethylmethacrylate (PMMA), and high-impact polystyrene.

5. A thermoplastic composite according to claim 4 wherein said outer polyester layer comprises an inert mineral filler.

6. A thermoplastic composite according to claim 5 wherein said outer polyester layer comprises an inert mineral filler comprising barium sulfate.

7. A thermoplastic composite according to claim 6 wherein said outer polyester layer comprises from about 10 to about 40 percent by weight poly(butylene terephthalate) or poly(ethylene terephthalate), aromatic polycarbonate from about 10 to about 25 percent, stabilizer from about 0.01 to about 10 percent, impact modifier from 4 to about 15 percent, barium sulfate from about 30 to about 40 percent, and additional ingredients including pigment or dyes present in an effective amount less than 5 percent.

8. A thermoplastic composite according to claim 7 wherein said outer polyester layer and said adjacent inner are extruded and have an overall thickness from 0.02 inch to 0.5 inch wherein the thickness of said polyester layer is from about 5 to about 85 percent of the overall thickness.

9. A thermoplastic composite according to claim 6 wherein said outer polyester layer comprises a thermoformed material comprising a two layered structure having a total thickness of 200 to 400 mils with an outer layer comprising polyester material and being 15 to 40 percent of the total thickness.

10. A thermoplastic composite according to claim 6 wherein multilayered material comprises a sheet having a two layered structure having a total thickness of 90 to 125 mils wherein said outer polyester layer comprises about 15 to 30 percent of the total thickness and said inner layer comprises an acrylonitrile-butadiene-styrene resin.

11. A thermoplastic composite according to claim 6 comprising at least a two layer polyester outer layer for having a decorative surface, said inner layer having different color than said outer layer, said pattern being developed by removal of a portion of the outer layer to expose said adjacent layer, said two layered structure having a total thickness of 90 to 125 mils wherein said outer layer is 15 to 30 percent of the total thickness and said inner layer comprises an acrylonitrile-butadiene-styrene resin.

12. A thermoplastic composite according to claim 6 comprising at least two layers, said outer layer comprises polyester and said inner layer comprises a mixture comprising an acrylonitrile-butadiene-styrene resin and a regrind mixture, said outer layer is about 33% of the total thickness.

13. A thermoplastic composite according to claim 1 comprising a three layer structure comprising an outer polyester layer, and adjacent layers comprising an acrylonitrile-butadiene-styrene resin and a regrind layer, said regrind layer comprising a mixture of polyester and an acrylonitrile-butadiene-styrene resin.

14. A process for preparing a decorative article comprising extruding a multilayered sheet by feeding at least two different resin compositions to an extruder, extruding said at least two resin compositions into the multilayered self-supporting coextruded sheet, and thermoforming at least a portion of said coextruded sheet into a decorative article wherein at least one exterior surface of the article comprising one resin and an adjacent layer comprises the other resin, said resin forming said exterior decorative surface comprising a chemically resistant filled polyester layer and an adjacent inner supporting thermoplastic layer for enhancing desirable mechanical properties of the composite.

15. A process for preparing a decorative article according to claim 14 wherein said decorative outer polyester layer comprises a colorant, an inorganic filler, an effective amount of a stabilizer, and optionally polycarbonate, n impact modifier, or a UV stabilizer, and mixtures thereof.

16. A process for preparing a decorative article according to claim 14 wherein the adjacent inner thermoplastic layer comprises a heat deformable layer having mechanical properties such as impact resistance and melt strength which desirably exceed these properties as possessed by the outer polyester layer.

17. A process for preparing a decorative article according to claim 14 wherein the adjacent inner thermoplastic layer comprises acrylonitrile-butadiene-styrene, polycarbonate, polycarbonate/ acrylonitrile-butadiene-styrene blend, copolycarbonate-polyester, acrylic-styrene-acrylonitrile, acrylonitrile-(ethylene-polypylene diamine modified)-styrene, phenylene ether resins, blends of polyphenylene ether/polyamide, blends of polycarbonate/polybutylene terephthalate and impact modifier, blends of polycarbonate/PET/PBT, polyamides, phenylene sulfide resins, poly(vinyl chloride), and high-impact polystyrene.

18. A process for preparing a decorative article according to claim 14 wherein the adjacent said polyester is selected from the group consisting of poly(ethylene terephthalate) ("PET"), and poly(1,4-butylene terephthalate), ("PBT"), poly(ethylene naphthanoate) ("PEN"), poly(butylene naphthanoate), ("PBN") and (polypropylene terephthalate) ("PPT"), and mixtures thereof.