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Mcrscburg, Sck lioii Cltrmic, UI)H-4200 Rlerscbburg * * ) Altadcniie clcr Wissenscliaflcn dcr DDH, Zciitralinstilut lur Orgaiiisclic Clicmic, UUII-1199 I;crlitiDurch Copolymerisation voii Cyclolicxyl~tic~ Itacrylat und Glycitlylittctltacryla~~ g c w o~i n c~i c polyrncrc Eposidc hilden in Verbindung mit einigcn Diaryliodonium-inid l'riarylsulfo~iiui~isalzeii anf (:r-bcsclticliI.ctcii Classubstraten Iiomogene transparcnk Schichtcii. Wiiltrcntl der 13cstrahluiig rnil Liclit tlcr Wclleiilangc 1 = 250 bis 300 nrn wird das Polymer durch die kationischcti I'liotolyscprocluktc der Oniurusalzc vcrtictzt. Die Sulfoniutnsalze sirid dabei effcktivcr als die Iodoniumsalze. Fur cine optimalc Vernetzutig ist cin wenig iiucleopliiles Anion, wie z. 13. Hexafluorophosphat, notwendig. Die Bildung des Ka talysators Itann tlurcli An thracen, 9.10-Phcnantlirciichiiion, Benzoplienon und Benzoinisopropyletlier sensibilisiert werdcn, womit tlcr E:inpfiiidlichkeitsbcrcich dcr Laclcsysteme auf 360 bis 420 rim ausdehnbar ist. Die Empfindliclilteit dcr Systemo is1 vcrgleiclibar mit dcnen aiidcrcr, bercits vcrwendcter Pliotopolymersysteine. @omounuyuupooaitrioe cuuouiiue nonujuepiioso 3iiolzcui)o OtiueobijUu COARMU I I o n m e p H b I e a n o~c n~b~, nonyqemme C O I I O J I H M~~H~~I J H~I % I~ylKJIorCI-FCAJIM~TaKI)MJiaTa II r n m q H f i m M e T I'l~otoinduced crosslirrking of a polyrtrcr cpoxide by orriiitu sulk l'olyrncric epoxides produced by copolyirierizatioii o f cycloliexyl iric~lii~cryla~c aiitl glycidyl nrc~liacrylate ~'OPIKI logcl.licr with diaryliodonium salts and triarylsulfonium salts clear coatings on (;r-surfaccs. A 1. irradiation with 2 = 250 t o 300 rim1t h e polymer is crosslinked b y the calionic photolysis products of tlic oniurn salts. T l i c sulfonium salts are more effective initiators tlian iodoniiim salts. For fast crosslinking a less nuclcopliilic anion, c.g. Iicsafluorophosphatc, is necessary. The catalysator forma tion can be sensitized hy atitltmcetic, '3.10-phenaiitlircric quiiiotic, bcnzophcnonc, and bcnzoinisopropyletlicr. The sciisitivi! y of tlicsc systcnis is similar 1.0 other used pltotopolyiiicr syskiris. EitileitiirigDurcli die erl18litcit Anforderuugcii i i i t (lie itiil~ro~~l(~ltli~o-nisclicn 13auclcinciitc stcigeii auclt clio A i i l ' o i~~l~~t~i~i i g e t i ati die zu ilircr IIerstrllirtig vcrwendetcti I'lio~olaclic 11, 21. 1)icsbczuglicli siiid insbcsondcrc Verbcsserungcn in der 1':iripfiiitlliclikei~. u i t t l i r r i nriflosungsveririogeii gefragt. Kiiic Vor1)csscruiig dcs AulI~suiigsvcrinijgens ist gruiidsiitzlicli (lurch vitic Vcrliiirzuitg drr I)cstraItIurigsweIIenIHnge crzichar. ~c r i i~x r g a i i g zur I: V-I,ilhographic crfordert bci Lacken, die itaclt dctn l'rinzip tlcr pliotoinduzicrlen Vernetzung arbcilcn, cine sclir gulc Alstiiiiinung zwisclicn den Eigeuscliafteii tlcr I'liotoi~ii~,ia~i~rc~i untl tlcr zu vcrnct.zendcn l'olyincrkomponeiitc. Wcrin dic Enipfiiidliclilicit dcr 1nit.iatorcn i n i ~~cllctilangctibercicli 2 < 300 i t m licgt und das l'olyinersystctn in dicscin Bercicli o...

Plasma treatment changes the solvent absorption and permeation as well as the swelling properties of polymers. Enchanced solvent absorption and swelling are effects of an improved solvent compatibility. The plasma introduces a large number of different groups at the polymer surface depending on the nature of the plasma. Fluorine-containing plasmas can replace hydrogen atoms of the polymer molecule with fluorine atoms. Moreover, fluorine-containing plasma polymer layers can be formed. All these processes reduce the resulting surface free energy, reduce the diffusion length of solvent molecules, and produce a barrier layer. We have studied the formation of solvent barriers by plasma fluorination and by crosslinking by ultraviolet (UV) radiation. Thin foils of polypropylene (PP) and polyethyleneterephthalate (PET) were used as substrates. CF4, SF6, and SOF2 were applied as sources of fluorine atoms. Hexafluoropropene, tetrafluorethylene, and perfluorohexylethylene form plasma polymer layers on the polymer substrates. Test solvents were n-pentane, tetrachloroethylene, dimethylsulfoxide, and mixtures of n-pentane and methanol. The permeation rate of solvents through plasma-modified polymers was measured gravimetrically. Mass spectrometry was applied to analyze the permeating components of the solvent mixtures. Fluorination of surface layers by plasma-chemical (CF4, SF6) means considerably reduces the permeation rate of PP (95% barrier effect) and PET (100%). The preferred permeation of one component of the pentane/methanol mixture is influenced by the polarity of plasma-introduced groups at the polymer surface.

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Die UV‐Vernetzung in 1 μm‐Schichten aus Polymeren verschiedener Konstitution, die 10 Gew.‐% 4,4′‐Diazidobiphenyl (DABP) enthalten, wird zeitabhängig anhand der reduzierten Schichtdicke nach Lösungsmittelbehandlung verglichen. Für die hohe Vernetzungsgeschwindigkeit von Polyglycidylmethacrylat mit den photolytisch gebildeten Bisnitrenen sind die 1,2‐Epoxypropylgruppen verantwortlich. Der Oxiranring bleibt erhalten (IR‐Spektroskopie). Wahrscheinlicher Reaktionsort ist die exocyclische CH2‐Gruppe (13C‐Festkörper‐NMR‐Spektroskopie).