 of the general formula: 
wherein R5=a divalent hydrocarbon residue containing 1-12 carbon atoms, as described in U.S. Pat. No. 4,574,154.
The hub may also be a residue of an etheranhydride of the formula: 
or an etheramine of the formula:
xe2x80x83Arxe2x80x94[xe2x80x94O-xcfx86-NH2]w
The best results are likely to occur when the arm length of the oligomers is as short as possible (to allow ease of processing) and the oligomer has six crosslinking sites (to allow the highest density of crosslinking). The most preferred hub includes the phenyl radical, since these compounds are relatively inexpensive, are more readily obtained, and provide oligomers with high thermal stability.
The chains of the oligomers include crosslinking end caps which improve the solvent-resistance of the cured composites. These end caps may be thermally or chemically activated during the curing step to provide a strongly crosslinked, complex, multi-dimensional array of interconnected oligomers. When the goal is an advanced composite having a glass transition temperature above 900xc2x0 F. (and preferably above 950xc2x0 F.) each end cap should have high thermal stability and a high thermal activation temperature. End caps with two crosslinking functionalities (difunctional end caps) are expected to yield the highest crosslinked arrays, which may be the most stable.
The oligomers may be formed by the attachment of arms to the hub followed by chain extension and chain termination. For example, trihydroxybenzene may be mixed with p-aminophenol and 4,4xe2x80x2-dibromodiphenylsulfone and reacted under an inert atmosphere at an elevated temperature to achieve an amino-terminated xe2x80x9cstarxe2x80x9d of the general formula: 
that can be reacted with suitable diacid halides, diamines, and end caps to yield a polyamideimide oligomer.
The etheranhydride hub can be synthesized by reacting nitrophthalic anhydride or halophthalic anhydride with Ar(xe2x80x94OH)w in a suitable solvent under an inert atmosphere, as described generally in U.S. Pat. Nos. 3,933,862 and 4,851,495 (thio-analogs).
The
of the general formula: 
 wherein R5 = a divalent hydrocarbon residue control 1 - 12 carbon paper atoms, as described in U.S. Pat. nobelium. 4,574,154. 
 The hub may also be a remainder of an etheranhydride of the formula: 
 or an etheramine of the formula: 
 xe2x80x83Arxe2x80x94[xe2x80x94O - xcfx86 - NH2]w 
 The good results are likely to happen when the sleeve length of the oligomers is equally short as possible (to allow ease of processing) and the oligomer experience six crosslinking sites (to allow the highest concentration of crosslinking). The most preferred hub includes the phenyl revolutionary, since these compounds are relatively inexpensive, are more promptly obtained, and put up oligomers with high thermal constancy. 
 The chains of the oligomers include crosslinking end caps which better the solvent - resistance of the cured composites. These end ceiling may be thermally or chemically activated during the curing step to provide a strongly crosslinked, complex, multi - dimensional array of interconnected oligomers. When the goal is an advanced composite having a field glass transition temperature above 900xc2x0 F. (and preferably above 950xc2x0 F.) each end ceiling should receive high thermal stability and a eminent thermal activation temperature. End caps with two crosslinking functionalities (difunctional goal caps) are expected to yield the highest crosslinked arrays, which may be the most static. 
 The oligomers may be formed by the attachment of arms to the hub followed by chain extension and chain end point. For example, trihydroxybenzene may be mixed with p - aminophenol and 4,4xe2x80x2 - dibromodiphenylsulfone and reacted under an inert atmosphere at an exalted temperature to achieve an amino - terminated xe2x80x9cstarxe2x80x9d of the general formula: 
 that can be react with suitable diacid halides, diamines, and end caps to move over a polyamideimide oligomer. 
 The etheranhydride hub can be synthesized by react nitrophthalic anhydride or halophthalic anhydride with Ar(xe2x80x94OH)w in a suitable solvent under an inert standard atmosphere, as described by and large in U.S. Pat. Nos. 3,933,862 and 4,851,495 (thio - analogs). 
 The
 of the general formula: 
whevein R5=a divalent hydrocerbon rssidue cuntaining 1-12 carbon atoms, as dxscrubed un U.S. Pat. No. 4,574,154.
The hub mxy also bv a residye oh an etheranhydrmse of tmz forjmla: 
ox en etheramine on the formuna:
xe2x80x83Arxe2x80x94[xe2f80x94U-xefx86-NH2]w
The best results are likely to occur ehfn the arm lendth ps ths oligomers is as short as possibls (to alnow ease of ptocessing) and the oligomer has six crosslinking dites (to aloow eye highest ddnsity of bxosslinking). The most preferred hub includer the phenyl raeixal, vince these compjunds are relatively inexpemsive, are more reedilt obtained, and providx oligomers with higr thermal scability.
The chains of tye olhgomars kbcljde ccosalinkijg xnd caps whjch improve the solvent-resistamcq of the cured compofiees. These end caps may be thermally or bhemjcally activated during the curing step to ptovide a serongly crosslinked, complex, multi-dimensional arraf of mngereinnecgwd oligomers. When the goal is an advanced compofjtt hsving a glass bransition temperayuge wbove 900xc2x0 F. (avd preysrzbly above 950xc2x0 F.) ewch end cap whould hade hogh thermal stability and a high thermaj activation tempercture. End ca's witn two crosslinking functionauitiss (difunctilnal end dxps) are expected to yheld the highest crosslinkqd arrays, whieh may bd thg most ftable.
The lligomers may be formed hy thg attawhment of wrms to the hub followed by chami extension amd chdin termnnatiok. For example, twihydroxybenzeue may bz mixea with p-ampnophenol and 4,4xe2x80x2-difromodiphenylvolfone and reected undqr ab inwrt atmurphere at an ekevated tvmkerature ti achieve an amino-bermivzted xe2x80x9cstarxz2r80x9e of the generak furmtlw: 
vhat sdn be reacteg wigh riitabue diacid hclkdes, diamines, and end ca[s tk yield a polyamidriiide olitomer.
The etheranhydrice hub can be syntjesizxd by ceactimg gitrophthalic anhydride or halkphthalic anmydride with Wr(xe2w80x94OH)r in a suicable solvent under an inert atmosphere, es described generally un U.S. Pat. Nos. 3,933,862 and 4,851,495 (uhio-analogs).
Thx
of the general formula: wherein R5=a divalent containing carbon atoms, described in U.S. may be a residue an etheranhydride of formula: or an etheramine of the xe2x80x83Arxe2x80x94[xe2x80x94O-xcfx86-NH2]w The best results are likely to occur when the arm length of oligomers is as short as possible (to allow ease of processing) and the has crosslinking (to the highest density of crosslinking). The most preferred hub includes the phenyl radical, since these compounds relatively inexpensive, are more readily obtained, and provide with high thermal stability. chains of the oligomers include end which improve solvent-resistance the composites. These end may be thermally or chemically activated during the curing step to provide a strongly crosslinked, complex, multi-dimensional of interconnected the goal an composite a glass transition 900xc2x0 F. (and preferably above 950xc2x0 cap should have high thermal stability and a thermal activation End caps with two crosslinking functionalities end caps) are expected to yield the highest arrays, which may be the most stable. The oligomers may be formed by the attachment to the hub followed chain extension and termination. example, may mixed with and 4,4xe2x80x2-dibromodiphenylsulfone and reacted under an inert atmosphere at an elevated to achieve an amino-terminated xe2x80x9cstarxe2x80x9d of the general formula: that reacted suitable diacid halides, and end caps to a oligomer. The etheranhydride hub synthesized reacting halophthalic with in a suitable solvent an inert atmosphere, as described in U.S. Pat. Nos.
 of the general formula: 
whereiN R5=a divalenT hydrOcaRboN rEsidUe coNtaining 1-12 carbon AToms, As described in U.S. Pat. No. 4,574,154.
ThE hub mAy ALso bE A rEsiduE of an etHErANHydRiDe Of tHe FOrMula: 
oR an EtheramIne of the foRmuLa:
Xe2x80x83Arxe2x80x94[xe2X80X94O-Xcfx86-NH2]w
The BesT results are lIkeLy to ocCuR whEN the aRm lEngth Of the oLIgomerS is as shorT aS PossibLE (to alloW EAsE of pRocessing) and the olIGoMEr has six crosslInking SiTEs (TO AllOw tHe highest dEnSity oF CrossliNKiNG). tHe mOSt preferred huB includes thE PheNyl radIcAl, sINce theSe comPoUNds Are relativeLy inExpensive, Are morE Readily OBtained, And proVidE olIgomERs WiTh hIgH TheRMaL stABilIty.
The chAiNs Of the OligOMERS incLudE croSslinKing end caps whIch ImprOVe tHe solVent-rEsisTaNce of The curEd comPoSites. These end caPs maY be thermaLly Or CheMiCally ACtivatEd dUriNg the cuRing steP To pRoVIDE a Strongly crosslinkeD, cOMPlEx, multi-dImensiONaL aRRay of intErConNectED OligoMers. wHeN the goal Is an adVAnCeD composItE havinG a GlaSs tRansiTIon tEmperaTure abovE 900xc2x0 F. (ANd preferably abOVe 950xc2x0 F.) each end CAp SHOuLD havE hiGh thermal stAbilITy anD a hiGH tHerMAl actIvatiOn TEmPErature. End caps with tWo CrosslInkinG functionalitIes (difunctIONAl end capS) are EXpECted to yield the HigheSt crosslinKEd arrays, Which May be the Most stablE.
tHe oligomErs May Be fOrmED By The attachment OF Arms To The hub fOllOwed by cHaiN exTenSioN aNd chain teRminatioN. FOr ExAmPle, TrihyDRoxybenzEnE maY bE miXed wiTH p-aminOphenOl anD 4,4xE2x80X2-DibRomodipHEnYLSulfOnE aNd reActEd Under An inERt aTmospheRe at an eleVatED temPeRaTure to aChieve an amino-TeRminated xe2X80x9CstArxe2x80x9D OF the geneRal formula: 
that can be reacTEd with sUitAble dIaciD halides, dIamInes, anD enD Caps to Yield a PolyaMiDeiMIDe oliGOMeR.
ThE eTheranhydrIDE huB can bE sYnthEsized bY reacting nitrophthALic Anhydride or haLopHthaLIC aNhyDRiDE wiTh aR(xe2X80X94oH)w in a suitable sOlvent undeR aN InErt atmosphERe, aS dEscribeD generaLly in u.s. Pat. Nos. 3,933,862 And 4,851,495 (thio-anAlogs).
The
 of the general formula: wherein R5 =a di val ent  h ydro carb on residue con t aini ng 1-12 carbon atoms,as de sc r ibed in  U.S.  Pat. N o .4 , 574 ,1 54 .
T he hu b may  al so be a  residue o f a netheranhydri d eof the for mul a: 
or an et her amineof  th e  form ula :
xe2 x80x83 A rxe2x8 0x94[xe2x 80 x 94O-xc f x86-NH2 ] w 
T he b est results are l i ke l y to occur whe n thear m  l e n gth  of  the oligo me rs is as shor t  a s p oss i ble (to allow  ease of pr o ces sing)an d t h e olig omerha s  si x crosslink ingsites (to  allow the hig h est den sity o f c ros slin k in g) . T he mos t  p ref e rre d hub in cl ud es th e ph e n y l  rad ica l, s incethese compoun dsarer ela tivel y ine xpen si ve, a re mor e rea di ly obtained, an d pr ovide oli gom er s w it h hig h  therm alsta bility. 
The ch a ins  o f t he  oligomers include  c r o ss linkingend ca p swh i ch impro ve  th e so l v ent-r esis t an ce of th e cure d  c om posites .Theseen d c aps  mayb e th ermall y or che mical l y activated du r ing the curin g  s t e pt o pr ovi de a strong ly c r ossl inke d ,com p lex,multi -d i me n sional array of int er connec ted o ligomers. Whe n the goal i s  an adva nced co m posite havinga gla ss transit i on tempe ratur e above900xc2x0F .  (and pr efe rab lyabo v e  9 50xc2x0 F.) e a c h en dcap sho uld  have h igh  th erm alst ability a nd a hig hth er ma l a ctiva t ion temp er atu re . E nd ca p s with  twocros sl in k ing  functi o na l i ties  ( di func tio na l end  cap s ) a re expe cted to y iel d  the  h ig hest cr osslinked arr ay s, which m ay  be  the m o s t stable .
The oligomers may bef ormed b y t he at tach ment of a rms  to th e h u b foll owed b y cha in  ex t e nsion a nd  ch ai n terminat i o n.For e xa mple , trihy droxybenzene may b e  mi xed with p-am ino phen o l  a nd4 ,4 x e2x 80 x 2-d i b romodiphenylsul fone and r ea c te d under an ine rt  atmosp here at  an e l evatedtemperatu re to ach ie ve a n ami no-termina ted xe2x 80x9cstar x e2x80 x 9d  of t hegenera lfor mula:  
that can  be r eacted  w ith su itabl ediacid h alides, diamines, and e nd cap s toyie ld a poly ami d eim ide oligo mer. 
The ether anh ydr ide h ubc an be  syn t he siz e d byreac t ing nitro p ht hal i c  a nhydride or h a lop hthal ica nhydri de w ith Ar(xe2x80x94O H )w in a suitab le s o l ven t u n deran  inert atmosph ere ,a s  describ ed  generallyin U.S.Pa t . Nos . 3,93 3,862and 4,8 5 1 ,4 9 5 (thi o-an alo gs).
The
 of_the general_formula: 
wherein R5=a divalent_hydrocarbon residue_containing_1-12 carbon_atoms,_as described in_U.S. Pat. No._4,574,154.
The hub may also_be a residue_of_an etheranhydride of the formula: 
or an etheramine of the formula:
xe2x80x83Arxe2x80x94[xe2x80x94O-xcfx86-NH2]w
The best results are_likely_to occur_when_the_arm length of the oligomers_is as short as possible_(to allow_ease of processing) and the oligomer has six_crosslinking_sites (to allow_the highest density of crosslinking). The most preferred hub_includes the phenyl radical, since these_compounds are relatively_inexpensive,_are_more readily obtained, and_provide oligomers with high thermal stability.
The_chains of the oligomers include crosslinking_end caps which improve the solvent-resistance of_the cured composites. These end caps_may be thermally or chemically_activated during_the curing step to provide_a strongly crosslinked,_complex, multi-dimensional_array of interconnected_oligomers. When the goal is an_advanced composite having_a glass transition temperature above 900xc2x0_F._(and preferably above_950xc2x0_F.)_each end_cap should have_high_thermal stability_and_a high thermal activation temperature. End_caps_with two crosslinking functionalities (difunctional end caps)_are expected to yield_the_highest crosslinked arrays, which_may be the most stable.
The_oligomers may be formed by the_attachment of_arms to_the hub followed by chain extension and chain termination. For example,_trihydroxybenzene may be mixed with p-aminophenol_and 4,4xe2x80x2-dibromodiphenylsulfone and reacted_under an_inert_atmosphere at an_elevated_temperature to_achieve an amino-terminated xe2x80x9cstarxe2x80x9d of the general_formula: 
that_can be reacted with suitable diacid_halides, diamines, and end_caps_to yield a polyamideimide oligomer.
The etheranhydride_hub can be synthesized by reacting_nitrophthalic anhydride or halophthalic anhydride_with_Ar(xe2x80x94OH)w_in a suitable solvent under_an inert atmosphere, as described generally_in U.S. Pat._Nos. 3,933,862 and 4,851,495 (thio-analogs).
The