@conference{
author = "Džunuzović, Jasna and Pergal, Marija and Poręba, Rafał and Ostojić, Sanja and Džunuzović, Enis and Špírková, Milena and Jovanović, Slobodan",
year = "2012",
abstract = "U ovom radu ispitana su svojstva poli(uretan-estar-siloksana) na bazi α,ω-dihidroksi-(etilenoksid-poli(dimetilsiloksan)-etilenoksida) (EO-PDMS-EO), 4,4'-diizocijanatodifenilmetana i alifatskog Boltorn® hiperrazgranatog poliestra druge pseudo generacije, kao umreživača. Sintetisano je pet uzoraka umreženih poliuretana sa različitim udelom mekih segmenata (EO-PDMS-EO) primenom dvostepene reakcije polimerizacije u rastvoru. Uticaj udela EO-PDMS-EO na mehanička i termička svojstva umreženih poli(uretan-estar-siloksana) ispitan je dinamičko-mehaničkom analizom (DMA), diferencijalnom skenirajućom kalorimetrijom (DSC) i merenjem tvrdoće. Dobijeni rezultati ukazuju da smanjenje udela EO-PDMS-EO utiče na povećanje stepena mikrofazne separacije sintetisanih uzoraka. Istovremeno dolazi do povećanja gustine umrežavanja, heterogenosti mreže i poboljšanja mehaničkih svojstava umreženih poli(uretan-estar-siloksana). Korišćenjem DMA određene su vrednosti temperature ostakljivanja mekih i tvrdih segmenata, kao i temperature koje odgovaraju sekundarnom relaksacionom procesu. Rezultati prikazani u ovom radu ukazuju da se kombinacijom makrodiola na bazi poli(dimetilsiloksana), hiperrazgranatog poliola i odgovarajućeg diizocijanata mogu sintetisati umreženi poliuretanski materijali odgovarajućih termičkih i mehaničkih svojstava za tačno određenu namenu., Properties of poly(urethane-ester-siloxane)s based on α,ω-dihydroxy-(ethylene oxide-poly(dimethylsiloxane)-ethylene oxide) (EO-PDMS-EO), 4,4'-methylenediphenyl diisocyanate and aliphatic Boltorn® hyperbranched polyester of the second pseudo generation as crosslinking agent were investigated in this work. Five samples of polyurethane networks having different soft segment (EO-PDMS-EO) content were synthesized using two-step polymerization reaction in solution. The effect of EO-PDMS-EO content on the mechanical and thermal properties of poly(urethane-ester-siloxane) networks was investigated using dynamic mechanical analysis
(DMA), differential scanning calorimetry (DSC) and hardness measurements. Obtained results revealed that decrease of EO-PDMS-EO content enhanced microphase separation in the synthesized networks. Simultaneously, increase of the hard segment content improved mechanical properties and induced increase of the crosslinking density and network heterogeneity of poly(urethane-ester-siloxane)s. DMA results revealed existence of two glass transition temperatures, of the soft and hard segments and the presence of secondary relaxation process. Results presented in this work indicate that this specific combination of poly(dimethylsiloxane)-based macrodiol, hyperbranched polyol and adequate diisocyanate can be applied to obtain polyurethane networks of good thermal and mechanical properties, which can be relatively easily
tailored for exact application requirements by changing soft/hard segment ratio.",
publisher = "Belgrade : Serbian Chemical Society",
journal = "Proceedings - 50th Meeting of the Serbian Chemical Society, Golden Jubilee Meeting of the Serbian Chemical Society, June 14-15, 2012, Belgrade, Serbia // Knjiga radova - 50. jubilarno savetovanje Srpskog hemijskog društva, 14-15. Juni 2012, Beograd",
title = "Mehanička i termička svojstva umreženih poli(uretan-estar-siloksana), Mechanical and Thermal Properties of Poly(urethane-ester-siloxane) Networks",
pages = "218-221",
url = "https://hdl.handle.net/21.15107/rcub_cer_6784"
}
