Influen€e of the unsafu lated benzoPhenone photoinitiators -t-

or
sz.zNin, PolyNer rn*ituh
Influen€e of the unsafu lated benzoPhenone photoinitiators
on shńnkage of acrylic pressure-sensitive adhesives
RAP]D COMMUNICATION
slmnary
ThE comnuni.ai€ pr€s.Ń a n.w Ćlass of ihe uńsaturated pho'
t ińihatoG ontainiĘ bel%Pheńone srolPs and lhen innlencc on shnnk.
ageof icrylicPPsule{elsiiiveadhe\ivcs(PsA)ołhdÓńPolyvinyl.hloride
(Pvc) ljlm. fte nuilr emPhasn is silcn to .hc innuen.r ol thń ncw das oI
.opolymc zble phobinitja\ns on shlij]kJge prÓ.ess ol a.Iyfic rsA afbi
-osłilkilrE with W lJńP Morcovcl, thc iŃluaft5 of various faĆtoĄ s!.h
'.'ośli''jirB' n' łld 'o ' ltn'o' ol'opolyń'
J''].Ąp'''P' lF.J ]-'' v'''c'l nol' 'l ''''g'a' d '
'''\
i€c on'Pl'
Pvc liln włe di{uscd
Kgy wddsi Jnńfońkd Phdoiniii oB' Lrv-dÓŚ linkin8, Pn$lrescNihYc
adhesiv*, aqyrabt shrinkiSc.
Uv_i'du.ed cÓs9linkin8 js ł nPidN w ening lsh
nol%yinpreslr-scEihvcadhesivs (Psa)a@ du o
.nr rec PrNs, cffi
cient and cconomi.il cncBy used łnd ncw FoPoiies
aM qLalityof cheni.ally.a$ Iinkinsbofdingitl.This
d.ślinkjĘ prces
lound inlel.shng rPPlicaiion 1ol
pr.d!.jng Phoiorea.tivĆ PsA sFlcms wiih high pet
fÓlnżn.c usctl in tI. Óating ol PVc su a.es
Thc idea ol replłĆing th. .onvcntioMl h'o pa* lhg
ndly aoŚ linked syshDE lvilh single.ońPon.nt .oom
tcmperafure UV achv cd PSA h€
Thg ńo* mPo ani fełtures of ihc crcsy]inked
pol]rłdylatc PsA, $'ch as la.k, Źdheson, cohBion and
Óf <,utc shlilka8e c 1 b. .onbollcd by the Lrv dcage'
cr.{glirking of PsA lvnh !ltaviolct li8hi .an be dÓne
dncdly afhr the apPliĆahon Mc.ory limPs (low, ńc
di!fr'^hi8h pleŚurc) of Powo b
w/cm_ arc used' Liv {atjons i]tlude sii ańd ńorc UV
lańPs wiih a polrd r20 io2'ow/.m2'
NonłI]y Polyad]rlats ibsorb the .ńt'c llght bcIow
300 nn I'r order b a(onrplish acĆ.ptableaos]i|kiq
xlth kansparenr PsA, only w wavelensrhs abovc 3oo
nm ale ińPotanl lI 8cnerali eńelg} 350_410 kjlmol h
re,trned ro. stinulaiion rr b.nzophcnon. tr.rivariv.s,
whi.h .omspond io w wav.rensrh nnge .bo!t 300 r)
]n-casil8 atEntn,n śEvcn
to a ne
rarcd .omPo]yneriŻablc Photoil]i
msizrhoi
v jlh
othcEidvh.mÓn.ń!a\'
honorrheprop(hcs r.f..lltr lrdac)
!onhii inx thcsc phoroin hibF n
5y
and
'n!c*'gJ.
rhcnzcd psA
1']'. oos_linking ń.chrnism of r]qr' PhobĘa.rjvc
łdylic PsA .ontainins Photorerdive beMoPhdDnc dc
rjvativs has beĆń iholou8hly iN6tigat.d lse lc'dion
-.T.--
-t-
t-l
\)
l)uring Uv .XPosiiion dt jntńolc.u]il benzoph+
nonc delivańves, showing H a(.P
.iied and rea.t vith $e n.iElbourins c-H posiiioN or
polymer Śidc .hains. Uv aos.]inkablc acr],li. PsA
Iitl'olrirc
sasahosPhcrctit.
Thc aim ol pr$cnt study was io inve*is3r th. Nfhr
cn.c oI the kind and łmountoILnsafulabd Phoioinitii
tot
bas.d Ón benzoPhenone and
shńnka8P01aqyli.PsA,aswonaŚ rh.n\iscoshś (mo
The
vis.cty oi synthcazcd solvc
compiny Molccu li r wcig h r 1ł.,)
was dctcrnnred usin8 HPlc{vsicm with Isosati.
PunP & DRl Dol€lor łon HF comp ]y'
Rhcoń cbic scicnhfi.
2 Ethylhex]rl adylafo
acylic
ac
(z-EHA' ńethyl adylat. (MA),
(AA), etlNl a.Ptaie (EA) and 121a2ołikc
werĆ purchas.d hom Tolyo
buiylonitilc (AlBN)
ch€miollndusbyco
(laPan).
Unsatlnted henzophcnoncs such as aadyloyloxy
bcnzoPhcnonc (ARP) (l' + (2 adyloyloĄ'.oxycth ylmc)
benzoph.nonc (AEBI') 01' a Q aĆryloyloxy-oxybuły-
"-""i"11t9
,.,=',.ro r.",,, .1 >ro
'1 ,> -Ll
chenitc. cnbH (Gemanyl
'lhe bad.
we
igl
Thcinnucnmsol drcrn.cnbahon or dirlclcntop,r
benzoPhrnone photoilitiatoA on thc vi5
msity łnd nolĆ.ular weight of thc
Iymerizabl€
,''
l.nc) bcvophcnon! (ABBP) (lll) and.l-(2-auyloyloxy
.oxyhcxylcfc) bcnzophcnonc (AHBP) (lv) ap synihcsi2ed by
vis.osity łn'l nok rular
Fł 1' E||.d t pk,oililhlal knrd d
|i:as !: 1 _ ABP, 2' AEBŁ 3 _ ABBP' 4
AlrBI'
włs synthesiz.d as. rcsult ol AIBN
'lsA
wi. 1) ,nitiatcd
.oF.lymrrization ol62-64.9/
2.EH,Ą,30'|] M^,5.% AA in lhe P
copolymcriablcbcnzoph.none phoroin iatoE lO,0D,
(llI)or(lv)l ilrEA'coPolync.izań(
2 holrŚ ar boilinE fonPcnfurc of thc solveńt lól Thiś
w.y solvot bas.d PsA w6e synihsiad wiih solld coń
(0.1
Thc invc*igitcd PhÓrÓlea.iivc Uv{ross_lilkcd
I€As tvffc orcd ]mrh ulfuViolł ]iEhi lamp (U 350'M.l'
-DL hom lsT conrPany) with Uv A wavelłrBih
clss
linking
v dose ]00 ńjl.m'
rried out IŃń tcńPsafur.' c!ri'1g
sfuinłaBe ptBenb ihĆ Pcrccntage.hang. of
sions or rhe liln .ovcrcd virh U
a.d atbĆhPd tÓ dt. Elas ifter kccP
dine}
Fi! I Etrit t tthnaititir,at kn tnn
DoLnkr .ń3tl M": cnfu- dts.,iłi,1 rs
n) FiŚ'
1
rh.nuc clnunsafuratcdbenŻoPhenomanouŃ
ofesPonds With thclnc65c iń PsA VlsĆosil'
- rhc iluctrc in unstur.tcd bcnz
incr.ases ihe hoL.ular weighi of Ps ,
lron thĆ nlve*i8ated U$ unt.d bc|Z.Phcmnc\
rhe higho* lalu.s or rsAs vis.o
weĘh b w.r. sjveń by benzo phcno
Trl. influen.e of the on.cnbahon of diffdńt !n
stuBtud beMophenone phdoiniiiaioE on PSA sh.ink
is shoM in Fig
aEe, at the śańe ooŚInriĘ ihe (ó0
',
shrinLase at ihc
sl.bilirer
bqi.ning rapidl
on and
dri"8
iime,
on ńe level far lower than inih'l onc
Ir genaal rh. use oI uNaiuratpd b.nzophcnons as
PhÓbinniators offe6 an interesiĘ aliernativc io lhc
olh* ńed'ods ol lcduong th. shtjnka8e o{ PsA coakd
on PVC lilms. The bsi r6ulb with
are obsNcd h rhe cme or ABP. F
a8e of PsA w* loNs
and.tĆlly shrinka8e <
by Ónsigneo of synrh6i2ed PsA with high
t]tan 0'5'r.
quir€d
Pa.
Iornan.! for Pvc slr{aces. sin'lally loł' valuc of
shrinka8enÓbhiń.dinrhe.asco{EinB1 wt ljoIABf
Fii 3' shrł'krF *ptlaui dl phd
Irlfrtian (.nŚ lilkil( l)j)Ł 6a n; cm6 ds.'il'.tr i5
liŚ 1,ddfun]ń IdD shri]tjŚI hul
d benzophenone
the shrinb8e
Pholoinitiators, the bst rcsulścon€lning
''
of this phoromriaror in rhc amouni as low as 0 75
similarly low shrinka8e valle fol
l.ng
ra.h
F)|t
4 shli1kay dtpt d.lc l łE!h*nĘ rńt
h,;!n
af p]nlah1itfulal
1,dolkdhE
1!|'%):.!rus d.sgłt;ln
Ifu shliłn|ż hD{1
sPl€ct€d
(] 0
.oncenhation of
u!'
wt 'Ł)' s. with lhc in'
wt
91,
guaĘntcs thc s islyin8 value of shrinki3c !c..hń3
ju* for.uring hme 60 s. For thc orhcr phoiornitDrors
Used, high6 conentatioB o1 lhem are n€edcd to re..h
ion of ĆurinE tińe !P
shdnkase valuc <0 5!r
1
Czc.h Z.:'Cros-linking
s.
Par.
l'vo e1l11
b
or
353 oee3)
driĘ
t,I0
r3,0
Aay
time ó0
wt.
/o
s Howthe
Pr