Isozianato gabeko poliuretanoen sintesia karbono dioxidoa erabiliz

Abstract

[EU] Giza jardueraren eraginez atmosferan aurkitzen den karbono dioxido kontzentrazioaren igoera nabariak aldaketa klimatikoa bizkortzea eragiten du. Honi aurre egiteko, CO2 kantitatea murrizteko prozesuen garapena oso garrantzitsua da. Ekimen garrantzitsuenetako bat, isozianato gabeko poliuretanoen (NIPU, non-isocyante polyurethanes) sintesia da, non gas hau erreaktibo gisa erabiltzen den. Ohiko poliuretanoen sintesia burutzeko, isozianato monomero toxikoak erabiltzen dira. Hori dela eta, karbono dioxidoa erabiliz, polimero berde eta jasangarriagoen sintesia egin daiteke. NIPUen sintesia aurrera eramateko epoxidatutako konposatu bio- oinarrituetatik abiatzen da orokorrean. Konposatu horiek, karbono dioxidoarekin erreakzionaraziz NIPUen sintesian ezinbestekoa den monomero karbonatatua lortzen da. Honenbestez, lan honetan soja-olio epoxidatuaren (ESBO, epoxidated soybean oil) karbono dioxido fixazio bidezko erreakzioa aztertu da, katalisi homogeneo bidez, soja- olio karbonatatua (CSBO, carbonated soybean oil) sintetizatzeko, zeina NIPUen sintesirako monomero nagusia izango den. Erreakzio baldintzak aldatzen joan dira, baldintza optimoena aurkitu arte. Optimizazio horrek energia eta baliabide gastua ahalik eta baxuena izatea du helburu. Olio karbonatatua diamina desberdinekin erreakzionarazi da NIPUak sintetizatuz, eta diaminen eragina aztertuz. Ostean, NIPUetan lortu diren propietate mekaniko ahulak hobetzeko, trimetilolpropano triglizidil eterra (TMPTE) eta karbonatatutako trimetilolpropano triglizidil eterra (CTMPTE) erabili dira. Monomero horiekin eta 1,4-diaminabutanorekin, CSBO/CTMPTE kopolimero karbonatatu eta CSBO/TMPTE epoxi/polihidroxiuretano polimero hibridoak sintetizatu dira, horien homopolimeroez gain. TMPTE eta CTMPTE monomeroen proportzio desberdinak propietate mekanikoetan duten eragina aztertu ondoren, argi ikusi da propietateen hobekuntza eman dela

[EN] The notable increase in the concentration of carbon dioxide in the atmosphere due to human activity causes climate change to accelerate. To face this, the development of CO2 reduction processes is very important. One of the most important initiatives is the synthesis of non-isocyanate polyurethanes (NIPU), where this gas is used as reagent. The usual polyurethane synthesis is done using toxic isocyanate monomer. So, using carbon dioxide, more green and sustainable polymers can be synthesized. NIPU synthesis is generally based on epoxidated bio-based compounds. The carbonated monomer, which is crucial for the synthesis of NIPUs, is obtained by the reaction of those compounds with the CO2. In the present work, the carbon dioxide fixation reaction of epoxidated soybean oil (ESBO) has been studied, through homogeneous catalysis, to synthesize carbonated soybean oil (CSBO), which will be the main monomer for the NIPUs. The reaction conditions have been changed, for establishing the most optimum reaction conditions. This optimization aims to keep reduce both energy and resources. The reaction between carbonated oil and different diamines for synthesizing NIPUs has been performed analyzing the effect of each diamine. Subsequently, to improve the poor mechanical properties achieved in NIPUs, trimethylolpropane triglycdidyl ether (TMPTE) and carbonated trimethylolpropane triglycidyl ether (CTMPTE) have been used. With these monomers and 1,4- diaminabutane, CSBO/CTMPTE carbonated copolymers and CSBO/TMPTE epoxy/polyhydroxyurethane hybrid polymers have been synthesized, in addition to their homopolymers. After examining the influence of different proportions of TMPTE and CTMPTE monomers on mechanical properties, it has been observed that there has been an improvement in properties.