Dissertation to receive master's degree in organic chemistry
Key words:
Persian: Basarsh, condensation, composite, nanocomposite, anchoring
English: polymerization, composite, nanocomposite condensation, anchoring
Abstract:
In this research work, a type of polymer called 2-](para-tolyl)oxy[-4,6 dichlorotriazine was synthesized with ethylenediamine. In this project, the mentioned polymer is linked with palladium metal nanoparticles and can play its catalytic role in the agricultural and pharmaceutical industries. For this purpose, firstly, the monomer 2-](para-tolyl)oxy[4,6-dichlorotriazine was prepared, then the desired polymer was made with ethylene diamine by a two-step process of substituted cyanuric chloride, then the nitrogen groups were bonded with palladium metal in the next step. The interactions between palladium nanoparticles and nitrogen atoms in the polymer were investigated by UV-vis. The size of these systems was determined by dynamic light scattering (DLS). These complexes have a diameter of about 140 nm. Also, the morphology of the polymer matrix nanocomposite of 2-](para-tolyl)oxy[4,6-dichlorotriazine with ethylenediamine and metal nanoparticles placed on the surface of the polymer were determined by transmission electron microscope (TEM) images. These nanocomposites are in the form of interwoven wires on which palladium metal nanoparticles are placed.
Introduction
Today, an active and very important part of research is focused on the use of nanoparticles for biological observations, environmental correction, nanostructures and nanocomposites chemistry [1-2]. Nanotechnology [2] is the manipulation of materials in the field of atoms, which includes placing atoms in their special place and allows materials to be made that are lighter, cheaper, stronger, cleaner and with higher precision compared to higher dimensions [3-4]. Among these special places for placing nanoparticles, we can mention polymers. By providing suitable substrates for the placement of atoms on their surface, resins provide the basis for the formation of polymer-based nanocomposites [5]. Among these, we can mention the polymers made of triazine monomers with amine chains, the presence of nitrogen atoms in the amine chains of these polymers has provided the ground for metal nanoparticles to be placed on the surface of those polymers. Nitrogen atoms with their lone pair of electrons can act as a hook or anchor in the chain and trap metal nanoparticles, including palladium nanoparticles. In this research, an explanation will be given first about polymers and then several polymers that have been prepared from the cyanuric chloride molecule so far, and about nanoparticles and how to prepare nanocomposites from nanoparticles, especially metal nanoparticles and polymers on which nanoparticles are stabilized. 1-1- Polymers are structures with characteristics Unique
It is difficult to imagine the current advanced world without polymer materials. Today, these materials have become a part of our life and are used in the construction of various objects, from everyday items and general consumption items to precise and complex medical and scientific instruments. The word polymer is derived from the Greek word (poly) meaning many and (meros) meaning unit or part. Many polymers have also found wide applications in the pharmaceutical and medical industry, for example, polysaccharides are known as the main components of bioactives [3] with anti-tumor immunization features and other valuable medicinal applications [6]. Also, a group of polymers are used in drug release systems with controlled release or in connections, such as surgical sutures and bone fracture repair and implant capsules. Some polymers have high thermal resistance, which has led to high melting point and stability against oxidative degradation at high temperature [7].Such polymers are used in automotive industries, aerospace industries, electronic components, insulators, pipes, all kinds of filters, adhesives, home appliance industries, coating of special wires, etc. Such polymers are prepared from both organic and inorganic types, but organic types are more common and most researches by polymer researchers have been fruitful in this field. Another feature of polymers is providing suitable substrates for placing or bonding different atoms on their surface. In this case, the product will be a composite material with new features. This is one of the characteristics of most polymers that are classified in different categories. In terms of the parent industries, polymers are divided into four groups: rubber, plastic, coating fibers, and glue industries, and in terms of source, they are divided into three main groups, which are natural polymers, modified natural polymers, and synthetic polymers. Also, based on the structure, they are divided into four types of cross-link polymers[4], branched polymers, linear polymers, and dendritic polymers[5], which have unique nanostructures. They are classified, and explanations about them will be provided below. In cross-linked polymers, in addition to the bonds that put monomers together in a chain, bonds are also established with neighboring chains. Polymers with high crosslinks have elastic properties. Cross-linking leads to higher tensile strength, improved cutting, better flame resistance and improved mechanical properties at high temperatures. Cross-linked polymers are classified into two groups: natural and synthetic. From synthetic crosslink polymers, we can mention various types of plastics, and from natural crosslink polymers, we can name protein.
1-1-2- Multi-branched polymers
Multi-branched polymers are polymers with a dense branch structure and a large number of end groups. Multi-branched polymer molecules consist of repeating units derived from the central nucleus that are incompletely branched or have an irregular structure. [6]
Dendrimers are spherical and multi-branched nanostructures, consisting of repeating units from the central core. In these polymers, layers of linear units are connected to the core, and each of these arms is terminated with a multi-functional branched unit. The word dendrimer is derived from two Greek words Dendra which means tree and Meros which means part, hence they are called tree-like. Dendrimers are one of the best candidates for making nanotools. These spherical and branched nanostructures are outstanding examples in the revolution of nanopolymers, they were first developed in 1978 [8]. Nanocarriers, nanoreactors, nanomembranes, nanocomposites and nanoparticles are only a few of the nanoobjects made by dendrimers. Tolyl) oxy]-4, 6 dichloro thiazine these with ethylene diamine have been synthesized, these polymers are due to the chain of amine in its structure and the ability of the element nitrogen in the making link in the chain to the metals can absorb them. In this project, remembered polymer bonds with Pd metal nanoparticles and their catalytic role to play in agriculture and medicine. To do this, the monomer 2 - [para (Tolyl)oxy]-4, 6 dichloro thiazine this was taken after a two-step process cholorores cyanuric chloride replacement and polymers of ethylene diamine was then the department of nitrogen in the Next came the metallic Pd bond. Interactions between the Pd particles and nitrogen atoms in the polymer were determined by UV-vis.