Preparation and non-isothermal cure kinetics study of epoxy resin nanocomposites with amine and epoxy functionalized magnetic nanoparticles

Abstract

Amine-functionalized magnetic nanoparticles NiFe2O4@SiO2@Amine (AMNP), and epoxy functionalized magnetic nanoparticles, CuFe2O4@SiO2@Epoxy (EMNP) were synthesized in three steps. Homogeneous stable dispersion of AMNP and EMNP, at concentrations of 1, 5, 10, 15, 20 wt% in epoxy resin were prepared using stoichiometric amounts of 4,4’-diaminodiphenylsulfone (DDS) as a curing. The optimum ratio of AMNP and EMNP were found to be 5%, and these were investigated by the total enthalpy of the curing reaction using differential scanning calorimetry (DSC) thermograms at 10°C/min. The cure kinetics of epoxy resin-functional magnetic nanoparticles-DDS composites were studied using non-isothermal DSC thermograms at different heating rates (5, 10, 15, 20°C/min). The kinetic parameters of the curing process, such as activation energy ( Ea), pre-exponential factor ( A), and rate constant ( k) were determined using several non-isothermal kinetic methods: Kissinger-Akahira-Sunose (KAS), Kissinger, Straink, Flynn-Wall-Ozawa (OFW), and Bosewell. The kinetic curing values obtained with different kinetic methods are well-matched. The Ea values were calculated in the range of 59.80 to 65.94, 57.69 to 63.92, and 45.38 to 52.45 kJ.mol−1 for the DGEBA/DDS, DGEBA/DDS/AMNP, and DGEBA/DDS/EMNP systems respectively. Also, The A values, using the Kissinger method, were calculated to be in the range of 7.0 × 105, 4.0 × 105, and 0.2 × 105 S−1 for the DGEBA/DDS, DGEBA/DDS/AMNP, and DGEBA/DDS/EMNP systems respectively. The glass transition temperatures of cured resins were determined with DSC, and the surface morphology of the nanocomposites and also the dispersion of the nanoparticles were investigated using scanning electron microscopy (SEM).

The Influence of Pristine and Aminoacetic Acid-Treated Aluminum Nitride on the Structure, Curing Processes, and Properties of Epoxy Nanocomposites

“…The influence of pristine and modified AlN on the processes of the structure formation during the curing has been established in Figures 12 and 13 2. Analysis of the data obtained shows that an increase in the concentration of aminoacetic acid accelerates the process of the structure formation of the epoxy composite containing modified AlN [56]. observed increase in the maximum self-heating temperature of the composition from 105 to 120-128 °C was noted, Table 2.…”

“…observed increase in the maximum self-heating temperature of the composition from 105 to 120-128 °C was noted, Table 2. Analysis of the data obtained shows that an increase in the concentration of aminoacetic acid accelerates the process of the structure formation of the epoxy composite containing modified AlN [56]. Thus, the analysis of the results of differential scanning calorimetry of epoxy compositions showed that the addition of AlN nanoparticles functionalized with aminoacetic acid into the epoxy composition additionally initiates the polymerization process due to the participation of reactive amino groups in the polymerization reaction, while a decrease in the initial curing temperature and an increase in thermal effects of the polymerization reaction.…”

Investigating the Structure and Properties of Epoxy Nanocomposites Containing Nanodiamonds Modified with Aminoacetic Acid

“…The acceleration of the curing reaction, accompanied by the release of a greater amount of heat, implies the participation of NDs in the polymerization processes. The functionalization of NDs accelerates the curing reaction and increases the amount of heat generated, confirming the fact of chemical interaction between the functional groups of aminoacetic acid and the epoxy matrix [ 56 ]. This fact is confirmed by a decrease in the duration of gelation from 95 to 78 min and curing from 142 to 106 min, as well as an increase in the maximum reaction temperature by 12 °C.…”

Studying the Structure and Properties of Epoxy Composites Modified by Original and Functionalized with Hexamethylenediamine by Electrochemically Synthesized Graphene Oxide

“…Adsorption can lead to the retention of oligomer molecules on the surface and the slowdown of the polymerization reaction, as well as to changes in the structure of the material, for example, the formation of denser surface layers. Thus, when assessing the effect of a modifying additive on network polymers, it is necessary to take into account adsorption effects, which can change the kinetic and structural properties of the material [42][43][44].…”