| Popis: |
This thesis deals with a preparation of modified polypropylene. Modified polypropylene was prepared by reaction itaconic anhydride and compounds contain primary and secondary amino group (diaminododecane, aminoethylethanolamine and aminoethylpiperazine). Knowledge of radical and condensation modification of polypropylene were summarized in the theoretical part. New application of modified polypropylene ware summarized at the theoretical part as well. In the experimental part polypropylene was functionalized by grafting with itaconic anhydride during reactive extrusion. Extrusion was carried on the co-rotating twin-screw extruder (Brabender 25 DSE L/D = 34) at 230 °C and 30 RPM. Residence time of reactive blend was 3 minutes. The modified polypropylene PP-g-IAH) contained 0.5 wt% of itaconic anhydride. 2,5 dimethyl 2,5bis(tert buthyl-peroxy)hexane (Luperox 101) was used as a radical initiator. A ratio initiator/monomer was 1:0.6 (mol/mol). PP-g-IAH was used for condensation reaction with amino compounds in molar ratios IAH/amine from 1:0,3 to 1:1. This reaction carried out in single screw extruder (Betol 1825 L/D = 39) at 210 °C and 30 RPM. Residence time of reactive blend was 3 minutes. Fourier transform infrared spectroscopy was used for a calculation of reaction conversion and for description of new functional groups in the materials. This analysis confirmed the presence of amide and imide groups in the samples. Influence of amino compounds to polymer crystallinity was studied by differential scanning calorimetry. Termogravimetric analysis focused on thermal stability of prepared samples and changes of thermal stability was observed in dependence of additives amount. The rheological behaviors of modified PP were analyzed by measuring the complex viscosity. |
