โ Scribed by Neale, S. M.
No coin nor oath required. For personal study only.
Living orgntiist~is tlcpctitl for tltcir form iiiicl structure open the I)reseticc of ltigli polytiicrs,* wliicli, iiloiic iiiiiotig~t or,n;~nic itiatcriiils, esliibit. 1 1 i ~~l i i i i i i ~i i l strciigtli, rigidity, niitl elnsticity. Piirtly 011 this nccount~, rititl pirtly beciiiise of tTbeir itiiportntice iii tlic textile itltlustrics, the prccisc striictrirc of tlic liigli polynicrs is ii subject. of iiicrensitiy! interest niid ittiport~i~iec. Most of the i~iittiriil high poly~itcrs consist of litic:tr tiincrotiiolecules, the iinture of whosc Iiiiilding units is in geiiernl d l cstnblishcd. The dcterminntioii of thc size of tiic molcculnr chains, ho\vcvcr, is n prohletll \vtiosc solution is still iiicomplctc. 111 tlic cnse of cellulose, for iiistnncc, the huilcling units iirc F gluco-pyrntiosc units (C,J-Ilo05), wliicli nrc joined t o g c t h r into chniiis of i~nkiioi-ii length by tiiciitis of glucosirlc litikngcs t,lirougli tlic 1 : 4 . .
I11 thr clctertninntioii of t,hc tiioleculiir w i g h t or tiioleculiir clinin lengtli of cclliilosc oiic iiiust, first titkc into nccouiit. the. vnrinhility of t~lic tiinteriiil. Cellulose is 11 ilntiirnl product, and its divcrsit,y is socli tltrtt the esact ideiit~ity of tiny two sniiiplo~ could hiirtlly be cstnblishetl. Thc word '' ccllulosc " slioultl iiirleetl be rcgnrdcd ritthcr ns it collectivc itoiiii. A uscfiil itisight into this question froiu tlic purely cheiniciil viewpoitit is ol~taincd frotii II study of tlic enrliest stages of tlic dcgrudnt,ion of cellulosc. The very cnrefol work of Clibbcns niid his co1l:tl)orntors hns slio\vti tltnt. cotton cellulose uiitlergoes progrcssivc niodificritio~i~ wltcn trcntctl with ncitls or with oxidizing itgetits. JJI tlte cnse of acid nttnck tlic tcttsilc strctigt.11 iititl viscosity full, wherens thc reduci~i! power riscs in n closcly rclnted t~initiicr,~ prcsutnnbly o w i g to tlic li1)criitioti of rctliiciiig sugnr groups by t.ltc propssive hydrolysis of tile glucosidc linkages. I t is rcitsotinblc to suppose! t , h t the itvcr:ige clinin lctigtli of tlic sliglitly liydrolysctl celluloscs frills coatinitously ns Iiydrolysis proccctls. I II tlic osid-
๐ SIMILAR VOLUMES
## Abstract The degradation of cellulose to __lmw__ samples with $\overline {DP} \_{{\rm w}} $ varying from 15 to 130 is investigated. Cellulose samples prepared from the hydrolysis of regenerated cellulose fibers in dilute HCl possess $\overline {DP} \_{{\rm w}} $โ=โ50. Applying homogenous degrada