Polyurethane coatings with reduced flammability based on tall oil polyols for wood protection | Poliuretāna pārklājumi ar pazeminātu degamību no taleļļas polioliem koksnes aizsardzībai

English. In the present work, the efficiency of using flame retardants of two different types in polyurethanes based on tall and some vegetable oils is evaluated. Reactive bromine-, chlorine- and phosphorus-containing flame retardants: IXOL B 251 (Solvay), Saytex RB-79 (Albemarle), Levagard 4090 N (LANXESS) and PC FR 125 or PC FR 225 (Nitroil Performance Chemicals GmbH, Germany) belonged to the first type. Intumescent flame retardants: Ammonium polyphosphate Exolit® AP 422 (Clariant International Ltd, BU Additives), Pentaerythritol 98% ALDRICH (Sigma-Aldrich Co. LLC.), Melamin 99% ALDRICH, (Sigma-Aldrich Co. LLC.) and Melamine phosphate (Tianjin Aokatet Chemical Co, Ltd. China) belonged to the second type. A comparative study of two types of polyurethanes based on two types of polyols: esters of oils and triethanolamine, and diethanolamides of these oils had been preliminarily carried out. It has been found that polyester urethanes based on esters of oils and triethanolamine are thermally more stable than the similar poly(urethane amides). Poly(urethane amides), on the other hand, have higher mechanical characteristics. However, taking into account the higher thermal stability of polyester urethanes, exactly those were chosen for the further modification with flame retardants. The thermogravimetric analysis of polyester urethanes with the addition of different reactive flame retardants has shown that, for such a type of polyurethanes, the most efficient flame retardant is the phosphorus-containing flame retardant Levagard 4090 N. Polyurethanes with the addition of Levagard 4090 N have both the highest temperatures of the maximum rate of weight loss for the final steps of decomposition and the highest char yield at 700 °С. The best parameters in the tests of wood samples with the polyurethane coating on a cone calorimeter were also found for the polyurethanes with the addition of the phosphorus-containing reactive flame retardant Levagard 4090 N.

Latvian. Izpētītas mehāniskās un termiskās poliuretānu, kas iegūti no taleļļas un dažām augu eļļām, īpašības, izmantojot dažādas sintēzes metodes. Noteikti to vidū termiski izturīgākie poliuretāni. Ar koniskās kalorimetrijas metodi izpētīta ar termiski izturīgiem pārklājumiem pārklātu koka paraugu degamība. Novērtēta arī dotajos poliuretāna pārklājumos rūpniecisko bromu, hloru un fosforu saturošo reaģētspējīgo antipirēnu IXOL B 251, Saytex RB-79, Levagard 4090 N, PC FR 125 un PC FR 225 pielietošanas efektivitāte. Novērtēta arī tādu antipirēnu pielietošanas efektivitāte poliuretānos, kas termiski sadalās un uzpūšas: amonija polifosfāts, pentaeritrīts, melamīns un melamīnfosfāts. Konstatēts, ka no visiem reaģētspējīgiem antipirēniem visvairāk pārklājumu, kas iegūti no taleļļas polioliem, degamību samazina fosforu saturošs reaģētspējīgs Levagard 4090 N. Amonija polifosfāts, melamīnfosfāts un tā kombinācijas ar melamīnu arī efektīvi samazina poliuretānu degamību. Dūmu izdalīšanās no poliuretānu pārklājumiem ar antipirēniem, kas termiski sadalās vai uzpūšas, lielāka nekā pārklājumiem ar antipirēna Levagard 4090 N piedevu.