RESUMO
The combination of efficient and harmonious aza-Michael and thiol-Michael reactions in one pot is first reported for the convenient synthesis of thermo-, oxidation-, pH-, and CO2 -responsive polymers. The simultaneous two-type Michael reactions are proved to proceed smoothly without additional catalyst. The dithiol and diamine are involved in the copolymerization competitively and thus in a random distribution. A wide range of commercially available starting materials are utilized for the simultaneous two-type Michael reactions in one pot to obtain various responsive polymers with different structures. The cloud point of the thermo-responsive polymers is easily tuned by adjusting the copolymerization ratio of monomers or using monomers with different structures. Besides, the oxidation- and pH-/CO2 - responsiveness are also demonstrated.
Assuntos
Compostos Aza/química , Dióxido de Carbono/química , Técnicas de Química Sintética , Polímeros/síntese química , Compostos de Sulfidrila/química , Temperatura , Concentração de Íons de Hidrogênio , Estrutura Molecular , Oxirredução , Polimerização , Polímeros/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Solid alcohols based on waste cooking oil (WCO) and other edible oils (butter or soybean oil) were synthesized by a simple one-step method. The effects of sodium hydroxide (NaOH) dosage and type of oil on the combustion performances were explored. IR spectroscopy and micro-morphologies of the oil based solid alcohols were also studied. Results showed that, for oil based solid alcohol, use of an appropriate excess of NaOH and an oil with lower iodine value produced the solid alcohol with better combustion performance. Centrifugation produced the bottom waste cooking oil (B-WCO) with lower iodine value and the supernatant waste cooking oil (S-WCO) with higher iodine value. The B-WCO afforded solid alcohol with longer combustion time, higher melting temperature and relatively low combustion residue rate, whereas the S-WCO could be used for synthesizing biodiesel.