DOSLO DNE
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OPONENTNi POSUDEK
Doktorsk6 disertadni prace
Dynamics of liquid penetration into fibrous materials"
Ing. Bc. Eva Ko5t'6kov6
Textilni falntlta, T e chnicka unive rzita v Lib e rci
Disertadni prilce je zamdiena na teoretick6 a experiment6lni studium pniniku kapalin do poreznich materi6hi se zam6ienim na materi6ly vl6kenn6. Jde o zajimavou a aktuSlni problematiku s Sirokym aplikadnim uplatn6nim. Re5en6 problematikaizcenavantjena piedchozi prhce pracoviSt6 a d6le je rozviji. Pr6ce systematicky rozviji nov6 experimentalni postupy a experiment6lni data porovn6v6 s u_isledky simulaci avychozimi teoretickymi modely.
Pr6ce je netradidn6 rozddlena do tiech samostatnjrch d6sti, kdekaLdh d6st m6 svoji irvodni teoretickou pashZ, d6st s vlastnimi qisledky a shrnuti vysledkri. I pies toto dlendni je prilce piehledn6. Jednotliv6 d6sti jsou zamlieny na experiment6lni sledov6ni pniniku kapalin do
por6znich materi6lfi, d6le na simulace procesri sm6deni vedouci k rowov6ze a testov6ni dynamickych procesri. Posledni d6st je v6nov6na aplikaci ziskanych pomatkfi pro vl6kny vyztuLene polymerni kompozity. Soud6sti pr6,ce viak nejsou piesn6 vymezen6 cile.
Disertadni pr|ce je naps6na v anglidtin6 m6 piim6ieny podet stran - 96 + 2l stran piilohy.
Pr|ce je piehledn6, dobie graficky zpracovan|, ale obsahtje vyznarnn6 mnoZstvi form6lnich chyb, viz qidet n6kteqfch znich v d6sti vdnovand pfipomink6m. Autorka pracovala cilen6, povlrla spr6vn6 metody a postupy. Dobie je patrny velky objem experimentalnich mEieni a simulaci, o demL sv6ddi tak6 detne prezentace autorky na konferencich, ale piedev5im spoluautorstvi 10-ti dl6nku v impaktovanych dasopisech.
Prfce piiniSi nov6 poznatky, kter6 mohou b;it dale rozvijeny a piisp6ji k pochopeni dynamiky pniniku kapalin do poreznich materi6hi a mohou bj't vyuLity nejen pro vl6kny vyzt.tLene polymerni kompozity, ale tak6 napi. pro filtraci kapalin.
K pr6ci m6m n6sledujici piipominky a dotazy:
- Str. 30: M6rov6 jednotky je tieba odddlovat mezerou, viz mNm-r, Pas v textu. Kurziva je vydlen6na pro oznadenifyzlkfinich velidin a nikoliv mdrovych jednotek.
- Str. 30-32, Fig. 2.31-33: Jaklf byl pod6tedni objem kapky? Byl tento objem pro viechny testovan6 kapaliny stejnlf? Prod pr'finik testovacich kapalin (glycerin, glycerin/voda) nebyl sledov6n pro vdt5i objemy a delSi dasovi irsek?
- Str. 48,52, dislov6ni odkazri: Odkazy jsou dislov6,ny pnibdZnd podle prvniho vyskytu pomoci piirozenych disel, jejichZ velikost vzrfrs+6. Chybi odkazy naRef. 10, 11 a 13.
- Str. 48-52, kap. 3 a 3.1: V rivodu do problematiky neni vhodn6 odkazovat se na skripta, disertadni di diplomovou pr6ci a konferendni piispdvky.
- Str. 57.Fig. 3.11 : Chybi odkazna Fig. 3.11.
- Str. 61, Fig. 3.17 Lineirmi regrese pro kontaktni rihel by m6la prochhzet pod6tkem os
v hodnotd nula.
- Str. 65, f.8 zdola:,,... problem was described by the author ... inp7l".Ref.27 vSak obsahuje jin6 autory, viz str.'76.
- Str. 69, bod 3, Fig. 3.33: Rozdil mezi pouZitim konedn6 nebo nekonedn6 zasoby kapaliny by v5ak m6l byt pxrny pro men5i hodnoty kontaktniho rihlu, napi' 5''
- Str. 70,Fig.3.34: Pnib6h grafu pro r:2 pii C;0 je netypicky. Prod?
- Str. 75,kap.3.4: Simulace nezahmuji viskozitu pouZit6 kapaliny. Jak by tento parametr mohl ovlivnit VaSe qisledky?
- Str. 76, Ref. I a dalSi: Chybi rok vyd6ni publikace. Ref. 10 a 1l jsou uvedeny pod dislem 1 a 2. Ref. 25 jeukryto pod Ref.24.
- Str. 78, dislov6ni odkazri: Odkazy jsou dislov6ny pr&b6Zn6 podle prvniho ,.yskyt, pomoci pihozenych disel, jejichZ velikost vztisrA.
- Str. 80, i.26*,,... thermosetting (epor.y, polyamide, phenol etc.)" Polyamidy patii mezi termoplasty a fenol je krystalickA pevnf l6tka. MoZn6 jste m6la na mysli fenolick6 pryskyiice (fenoplasty).
- Str. 80, f.l6 zdola ,,... elasticity modulus ..." Spr6vnd mi byt,,elastic modulus", Young's modulus", piipadn6 "modulus of elasticity".
- Str. 89, Fig. 4.12'. "... the best fiber contents, about 34% ..." Prod bylo cilem dos6hnout maximflniho obsahu vl6ken?
- Str. 91, rormice uprostied strany: Rovnice umoZiluje u.fpodet pevnosti vohybu (flexural strength), coZ neni v textu uvedeno.
- Str. 91, Fig. 4.15'. Jake jsou mechanicke vlastnosti (modul pruZnosti, pevnost) PAN a PVA nanovlfken?
- Str. 95, Ref. 66: N5zev dl6nku je odli5nj' od zhznamu Web of Science.
- Appendix I" sloupec vlevo: Dle uveden6ho vztahu je qfika nepiimo irmdm6 viskozit6 kapaliny. Pr&bdh prostiedniho grafu tomu neodpovidi.
- Appendix V, VI: Popis grafi by m6l byt dostatednyf pro orientaci v grafech bez potfiiti textov6 d6sti disertace.
Prilce je velmi zajimavh a je ziejm6, Le autorka v6novala mnoho dasu rozs6hlym mEienim, jejich analyze a dasovd n6rodnj'm simulacim. ZhvErem shrnuji, Ze disertadni prhce prokaz,,fie piedpoklady autorky k samostatn6 tvurdi prilci a spliuje krit6ria kladen6 na disertadni pr6ci. Doporuduji tedy pr6'ci k obhajob6. Za piedpokladu spr6vn6ho zodpovlzeni dotazfi a risp65n6ho prfibdhu oponentniho iizeri doporuduji uddlit Ing. Evd KoSt'6kov6 titul Ph.D.
V BrnE dne 3. ledna2012
z7 .-r_
prof. RNDi. Vladimir Cech, Ph.D.
Ustav chemie materi6lfi, FCH Vysoke udeni technick6 v Bm6
dor. .,'*- fi. l. "zo za V6,
Ning Pan, Ph.D.
Professor in Fiber & Polymer Science Division of Textiles
Biological & Agricultural Engineering The University of California at Davis Email: npan@ucdavis.edu
Ph.D Thesis Review Report Thesis By: Eva Ko5t'fkovri
Area: Textile Material Engineering, Technical University of Liberec Title: Dynamics of Liquid Penetration into Fibrous Materials
This thesis deals with a subject highly challenging in science and critically important in practical applications.
The thesis first offered a rather complete review of the current research activities and the cutting edge on the dynamics of liquid penetration into porous materials, especially the existing theoretical models including the cylindrical capillary and radial capillary approaches.
There was also a part dealing with the enhancement of liquid penetration into porous materials with the intention of ultrasound usage. It further suggested that experimental endeavor should bring a design of a simple and an effective method for studying the dynamics of liquid penetration into fiber materials and testing for a scale of nonwovens with different geometrical parameters (change of fiber volume fraction, change of orientation of fibers, change of fiber diameter...).
The main focus of the candidate's own research is employing the automodels and Monte Carlo methods for simulation of wetting phenomenon in fibrous media. The candidate developed several computer simulation algorithms to model a few highly complex problems in wetting process in textiles. Experimental data have also been generated to confirm and verify the theoretical predictions.
The last part is devoted to nanofiber-reinforced composites, those reinforced by carbon nanotubes and electrospun nanofibers. The thesis introduced some technical issues in electrospun nanofibre web processing and composite manufacturing, including polymer selection and technical routes in making electrospun nanofibre, reinforcing mechanisms of nano-scale reinforcement in a composite, resin penetration into the nano-fiber web, ultrasonic and plasma approaches to facilitate impregnation of nanofibrous layers, and examination of the composite qualities and strengths.
