"polymerization; polypropylene; nanofiller; nanocomposite"@en . "2013-06-30+01:00"^^ . "0"^^ . . . . . "0"^^ . . "0"^^ . . . "V\u00FDzkum a v\u00FDvoj polypropylenov\u00FDch in-situ nanokompozit\u016F"@cs . "Polypropylene (PP) is a polymer with relatively low toughness and the addition of inorganic compounds (fillers) significantly increases it. However, a high concentration of common fillers with a particle size of tens of microns is necessary to achieve the required stiffening effect, which causes the adverse increase in the composite density. Applications of fillers with a particle size of tens and hundreds of nm allow preparation of nanocomposite materials with a much lower amount of filler, exhibiting high toughness and retaining low density. However, perfect dispergation of the nanofiller in the polymer matrix is necessary to achieve the stiffening effect. This is very energetically expensive if performed in an extruder. The suggested procedure for the dispergation of the nanofiller in the PP matrix performed directly in the polymerization reactor will allow the preparation of nanocomposite materials with significantly lower production costs."@en . "10255"^^ . "0"^^ . . . . "Research and development of in-situ polypropylene nanocomposites"@en . . "4900"^^ . "Polypropylen (PP) je polymer vyzna\u010Duj\u00EDc\u00ED se pom\u011Brn\u011B n\u00EDzkou tuhost\u00ED. P\u0159id\u00E1n\u00EDm anorganick\u00FDch slou\u010Denin (plniv) lze dos\u00E1hnout v\u00FDrazn\u00E9ho zv\u00FD\u0161en\u00ED tuhosti a pevnosti. V p\u0159\u00EDpad\u011B b\u011B\u017En\u00FDch plniv o velikosti \u010D\u00E1stic v \u0159\u00E1du des\u00EDtek mikron\u016F doch\u00E1z\u00ED k vyztu\u017Euj\u00EDc\u00EDmu efektu a\u017E p\u0159i vysok\u00FDch koncentrac\u00EDch, \u010D\u00EDm\u017E doch\u00E1z\u00ED k ne\u017E\u00E1douc\u00EDmu zv\u00FD\u0161en\u00ED hustoty kompozitu. Naopak, pou\u017Eit\u00EDm plniv o velikosti \u010D\u00E1stic v \u0159\u00E1du des\u00EDtek a\u017E stovek nm lze vytvo\u0159it nanokompozitn\u00ED materi\u00E1ly, kter\u00E9 umo\u017E\u0148uj\u00ED dosa\u017Een\u00ED vysok\u00FDch tuhost\u00ED a pevnost\u00ED PP ji\u017E p\u0159i v\u00FDrazn\u011B ni\u017E\u0161\u00EDch koncentrac\u00EDch. V\u00FDsledn\u00E9 PP materi\u00E1ly se pak vyzna\u010Duj\u00ED vysok\u00FDmi tuhostmi p\u0159i zachov\u00E1n\u00ED n\u00EDzk\u00E9 hustoty. Podm\u00EDnkou dosa\u017Een\u00ED ztu\u017Euj\u00EDc\u00EDho efektu je v\u0161ak dokonal\u00E1 dispergace nanoplniva v polymern\u00EDm materi\u00E1lu, obvykle prov\u00E1d\u011Bn\u00E1 v extrud\u00E9ru, co\u017E je v\u0161ak energeticky velmi n\u00E1ro\u010Dn\u00E9. Navrhovan\u00FD postup dispergace nanoplniva v PP matrici prov\u00E1d\u011Bn\u00E9 p\u0159\u00EDmo v polymera\u010Dn\u00EDm reaktoru, umo\u017En\u00ED p\u0159ipravovat nanokompozitn\u00ED materi\u00E1ly s v\u00FDrazn\u011B ni\u017E\u0161\u00EDmi v\u00FDrobn\u00EDmi n\u00E1klady."@cs . . "2009-07-01+01:00"^^ . "1"^^ .