3.1 Effect of reaction time period
The time course is a good indicator of catalyst performance and reaction progress. It helps pinpoint the adequate time necessary to obtain the best yield and minimize the process cost. Figure 1 shows the acid value profile of Sn(Oct)2 catalyzed synthesis of PRA. As the reaction progressed, the hydroxyl group of one monomer reacted with carboxylic group of another monomer to form oligomer and then the chain was lengthened to polymer. This was indicated by a decrease in the acid value of from 164 to 52 (mg of KOH/g sample). It was first time demonstrated that Sn (Oct)2 can catalyze the polymerization of ricinoleic acid. Earlier, Raia Slivniak et al [13] reported the polymerization of the ricinoleic acid lactones using Sn (Oct)2 a catalyst. In order to get optimized conditions for PRA synthesis, the reaction parameters such as temperature, catalyst concentrations, etc. were further investigated. Figure 1: Effect of reaction time period on PRA synthesis
[Catalyst cocn = 5% w/w, temperature of reaction = 150°C]
3.2 Effect of temperature
The reaction temperature is a crucial parameter in catalysis [14]; therefore, we selected four different temperatures in the range of 60–150°C for the synthesis of PRA (Fig. 2). It was …show more content…
From fig. 8 it was observed that as amount of methanol was increased, the acid value of PRA product decreased i.e. MW is increased. After 20 ml of methanol per g of PRA product, no significant change in acid value (25 mg/g of KOH) was seen and GPC analysis shown that the final PRA product (insoluble fraction) was homogenous with high MW (4026 ± 440 Da). All other molecules with MW < 4026 were solubilised and enter into an upper layer as methanol amount was increased. Thus an optimized ratio of methanol (20 ml/g of sample) to PRA product can be used for obtaining polymer with high
The time course is a good indicator of catalyst performance and reaction progress. It helps pinpoint the adequate time necessary to obtain the best yield and minimize the process cost. Figure 1 shows the acid value profile of Sn(Oct)2 catalyzed synthesis of PRA. As the reaction progressed, the hydroxyl group of one monomer reacted with carboxylic group of another monomer to form oligomer and then the chain was lengthened to polymer. This was indicated by a decrease in the acid value of from 164 to 52 (mg of KOH/g sample). It was first time demonstrated that Sn (Oct)2 can catalyze the polymerization of ricinoleic acid. Earlier, Raia Slivniak et al [13] reported the polymerization of the ricinoleic acid lactones using Sn (Oct)2 a catalyst. In order to get optimized conditions for PRA synthesis, the reaction parameters such as temperature, catalyst concentrations, etc. were further investigated. Figure 1: Effect of reaction time period on PRA synthesis
[Catalyst cocn = 5% w/w, temperature of reaction = 150°C]
3.2 Effect of temperature
The reaction temperature is a crucial parameter in catalysis [14]; therefore, we selected four different temperatures in the range of 60–150°C for the synthesis of PRA (Fig. 2). It was …show more content…
From fig. 8 it was observed that as amount of methanol was increased, the acid value of PRA product decreased i.e. MW is increased. After 20 ml of methanol per g of PRA product, no significant change in acid value (25 mg/g of KOH) was seen and GPC analysis shown that the final PRA product (insoluble fraction) was homogenous with high MW (4026 ± 440 Da). All other molecules with MW < 4026 were solubilised and enter into an upper layer as methanol amount was increased. Thus an optimized ratio of methanol (20 ml/g of sample) to PRA product can be used for obtaining polymer with high