Synthesis and characterization of polymers based on citric acid and glycerol: Its application in non-biodegradable polymers

Abstract

The notable increase in global consumption of plastics and their long residence time in the atmosphere show the great need for biodegradable products. In this project, we developed biodegradable polymers based on citric acid and glycerol. Their synthesis was carried out at different conditions of constant temperature and concentration and they were synthesized using an economically viable method. Characterization was undertaken using: Acid number, FTIR spectroscopy, refractive index, viscosity, impact analysis, tensile test, hardness, calorimetry, the % humidity (oven method with recirculating air), and density determination, along with qualitative evidence to corroborate their biodegradability. These elaborated polymers were mixed with medical grade PVC formulation, obtaining a hybrid polymer, showing their mechanical properties were changed.

Transparent Composites Made from Tunicate Cellulose Membranes and Environmentally Friendly Polyester

“…[8] The relatively high optical transparency obtained here should originate from the similarr efractive index for both cellulose (1.53) [28] and glycerolc itrate polyester (1.50). [29] This hasa lready demonstrated in wood-based transparent materials, in which the cellulose and the polymerf illed in with similarr efractive index reduced light scattering, resulting in an almost complete light transmission and opticalt ransparency. [28] Varying the ratio between citric acida nd glycerolh as been found to negatively affect the transmittance of the composites both when increasing and decreasingt he ratio from the equimolar state ( Figure 6).…”

“…By UV/ Vis measurement, the transmittances of the obtained composites were within the range of 60-70 %a t6 50 nm ( Figure 6). [29] This hasa lready demonstrated in wood-based transparent materials, in which the cellulose and the polymerf illed in with similarr efractive index reduced light scattering, resulting in an almost complete light transmission and opticalt ransparency. [8] The relatively high optical transparency obtained here should originate from the similarr efractive index for both cellulose (1.53) [28] and glycerolc itrate polyester (1.50).…”

Development of controlled release fertilizer systems for KCl using glycerol‐based polymers

“…Since the spectroscopic behavior of all controlled‐release systems explored here were quite similar upon changing KCl concentration, only results pertaining to pure PGC and compounds with 20 wt% KCl are shown in Figure 2. Pure homopolymers, copolymers, and their compounds with KCl have typical characteristic absorption bands of CO, C═O CH, and OH groups 32 . All polymers show a characteristic peak at 3300 cm −1 attributed to the stretching mode of the OH bonds; peaks at 2930 and at 2850 cm −1 , attributed to alkene groups; and absorptions at 1730 and 1707 cm −1 , due to C═O stretching mode, and the weak band at 1045 cm −1 characteristic of the alkoxy group that proves the formation of polyester 17 .…”

Analysis of the Effect of Processing Conditions on Physical Properties of Thermally Set Cellulose Hydrogels

“…A peak increase in the region around 3400 cm −1 for the neat solution indicates a higher concentration of hydroxides (OH) and thus pointing to a higher amount of glycerol present. This is an indication towards the reaction of excess ECH with itself resulting in the formation of glycerol instead of cross-linking bonds between cellulose [62].…”