Document peZymagwyZG5GO3rj8MnrbyN6

ntechnot., 21, 5 JOURNAL OF APPLIKD POLYMER SCIENCE VOL. 19, 3169-3172 (1975) Analysis for Vinyl Chloride in PVC Powders by HeadSpace Gas Chromatography A. R. BERENS, Corporate Research, B. F. Goodrich Co., Brecksville, Ohio 44141, L. B. CRIDER and C. J. TOMANEK, Technical Center, B. F. Goodrich Chemical Co., Avon Lake, Ohio 44012 and J. M. WHITNEY, General Chemical Plant, B. F. Goodrich Chemical Co., Avon Lake, Ohio 44012 Synopsis At * tmp*ritur above the gUu munition point of polyivinyl chloride) (FVQ, the solubility of vinyl chloride monomer (VCM) in PVC accurately follows Henry's lew behavior for VCM con tents up to 4000 ppm. This observation hss lead to a rapid, simple gas-chromatographjc method for the determination of VCM in PVC from the analysis of the vapor phase (haad-space) over PVC powder sample* in a saalad container. The basic axpsrimsntai techniques, calculations, and slamplea of axpsrimsntai data are given. The method can be used with any commercial gas chromatograph equipped with e flame ionization detector without instrument modification. INTRODUCTION Recent concern about the poesible health hazard of exposure to vinyl chlo ride monomer (VCM)1 haa focused attention on the measurement of residual monomer content! of commercial PVC products. We report here a simple, rapid analysis for VCM in PVC through gaa chromatography of the vapor phase over PVC powder samples. The basis of our method is the observation3 that at a temperature above the giau transition point of PVC, tha solubility of VCM in PVC accurately follows Henry's law behavior up to a VCM content of at least 4000 ppm. The analytical procedure simply involves sealing a weighed PVC sample contain ing VCM in a suitable vial at room temperature, heating tha vial to 90C to establish VCM equilibrium between PVC and vapor phases, and analyzing a syringe sample of tha "head-space" vapor for its VCM content. The original VCM content of tha PVC is calculated as follows: Let us say that tha PVC sample of weight m grams originally contains Wt grama VCM. Upon eqmhbration at 90*C, W, ro Wu + W,, (1) where Wu and Wp are the weights of VCM in"tha vapor and PVC phases, re spectively. We may write Henry's law as ~ 1975 by Juba Witoy 4 Sen*, lac. ^ = KPX. m 316* (2) a.*-. i,; ->/'-.< ucc 021855 W**sa rpm; ehavtta, it can t (3) r weight of VCM, of PVC itnpie), lumeZcr. Altar v be obtained dis chromatogram. m, directly front r and PVC phaa* Front Um mb- he data required 1 J` at in Uta tratjUn|,ed< of the VCM ... *-f<^fcTMitarwii^rdnchromatofTapfciB.<taWnawdbyu^ectingkDowi. atandtadi^itiHeeafvir^lcbtat^eand^r; Sampfcrforaial^arfc prepared hyweifbang apprombaately 2 g PVC powsfet into a ta-ddVftit anA aaaflwg |fra vial with a fold-over septum* Tba sample vials erethsnflbnsrl ip an ai^ovwo* watar bstfceantreiled at 90*0 amt allowed to squiiflic*t*> ' After equiKfcriutaJMa&abliahad, an aliquot of the vapor spans in the vial b renanad witbagaa-tiljbtajringe. The volume of thi* vapor sample at room timpTnafnn and jptapmta i# natad, and? the sample is iigected into the chro matograph for ana4paftt, Aea convanisnt alternate to manual ayringe-aam- plk* of the head-spece. vapor, w* have recently used an automated head- spaa* analyser fPdfW'Fbihd Modef'lMaJt Detamthatlon of the reaidual vtpfcahMay Wfl)a|pp^- fc-4 , ,,..w. - .v,V -AJwn^jP'; i-'-v >' > * { *- ..... ~' (4) :Xi ; ?; '' ion wdroiwt ta* X IQr*** fca^/bee; . _ in 2B jatarma ef> , acffQbw.jtawtad is ta-thn mpely. tarrt*moid*d, v UxcoquiMbnn k ' '' ' ; V-' . * .' ,, f|bdibitythe ais$tt^^tlb'haedbfc^ aw^^4|tffc aa stripped1 " cffijfejaiditat, vtejftdtWtda vta vopmm-tamTnal tsefcafcftsb , Head-spacer,, `'*" * --'**=^* - *e';- * '*$01. .TJ* ***'* ream- : stytttm sealed. Kfcewn amounta *' U^atBO-C, L-^ " >, ,Vt^ Table l* V "' .. ' > ' *a ^] y*> *- teetqgablMPG*.. w'to'&ttfeta. V >,d ;atograpptaa|^ \ - ;V n tfaahaadqppaa . ventai tiwe MtgK. * ' fthWMpaak-' maaaapacMna- .aX a. Ow SC-M8 -esins fra atwwn> is net-rotaplata- " cofcMA'Iftatean ' Sp ! i ''J,'^ ,, M1 -v. r.'^v ''..I . f',y' v*i*ta. . -i.1 ^ -> l%Wiipr rntmtiffi t*vQmh* ' fttalttat rf^ha-B-P 8^4^ ^ ofthq tab*. W *' < (iijiKStad 'An hank C. i'' r,: J T|f y 7 * ^r: ' I'- : y1 i ' . ' x;f =.- ;y;:-, 4- 5^^. -: * - St ` ucc 021357 r I ?v, T' v i. ' - - s-14 ' <.$ * ;'. >v v';4-'?<i ,-v .V\;-v-~ ' Co^pri64 oTjMd-Spm Wrt.:Oft<^r Ihrttodt .. \ </v :' * r ; ; Dtnctmtbo4tof iMiyafatjw* ' yvg fWiiaiLlnnlr"A* ' ^tV: 3rfTTf fcsr^ 'it,* -E_ ' 1 -v- 30 - - 4 ..>.. -V ,, 4* ' '... ,4477 4 5- ,.>' j' . 5M^Cv1;,^.V ` - *r *-' w,, . intfodnc pcnibto I^UlifrtiM celunw tamperatur tf,4afereiiient*iui* 4k* b*i-p** awthod. '* i .4. . `..W.sSrf k kf ", ' - _.. ,, i W*- " . * ySfcflBr . ' j* V,v -^:.'*?,4',V >! 1j > > ' ' ( n m -- ucc 021858