Strong hydrogen bonding interactions between amide groups back up some typical weakness of aliphatic polyester. The properties of polymer like hydrophilic or hydrophobic ratio and biodegradability easily adjusted. Synthesis of Polyesteramides: Polyesteramides can be prepared from different monomers and lead to random, blocky and ordered microstructures. The monomers of the polyesteramides are esters and amide bonds linked to each other, which have good vulnerability for
Metallacarboranes are artificial structures with distinct physicochemical properties, such as delocalization of cluster charge, high rigidity of the skeleton, lipophilicity and the ability to form so-called dihydrogen bonds. Di hydrogen bonds connect partially negatively charged hydrogen atoms bonded to electropositive boron atoms with the partially positively charged hydrogen atoms in organic
There is at least 85% polyurethane in spandex. In addition, the spandex elastomer which is characterized by better than rubber due to it’s robust, versatile, lightweight and easily stretched until 500% from its original length. Elastomer is a polymer that has a loose cross-link structure. This type of chain structure causes elastomers have the ability to return to its original shape after being stretched. This fiber has a structure that has soft segments and rigid segments such as figure
The two primary hydroxyl functionalities provide excellent reactivity during both the esterification process and the subsequent crosslinking reaction. Although the cyclohexyl ring is completely saturated, the presence of labile beta hydrogens lowers the exterior durability of polyesters based on this diol. Generally, this diol is used for its excellent contribution to hardness and backbone rigidity. Ni et al  and Awasthi and Agrawal  can be considered in both works, 1,4 cyclohexanedimethanol was used for the synthesis of hydroxylated
Figure 2. Representation of 1.3-butadiene (mw: 54.09 g/mol) Styrene: A colorless to yellowish liquid that produce polystyrene by homopolymerization. Styrene is a derivative of benzene and could be found in small quantities in plants and foods. It is slightly soluble in water and very soluble in ethanol, acetone and carbon disulfide. Its rate of polymerization is low at room temperature but increases at higher temperatures.
Bubbles are round because they are ‘minimal surface structures’, which means that bubbles hold the least possible surface area they can. Out of all the geometric shapes, a sphere has the least surface area. Bubble soap is mostly made of water, soap, and glycerin. Glycerin is an organic compound, and its common sources are animal fat and vegetable oil. It is a clear, odorless liquid, and has a sweet taste.
Polycaprolactone is an industrial polymer that has a very low melting point, and thus can be used for model making and prototyping. Polycaprolactone was selected for this study as it has been used previously for 3D printing meniscus scaﬀolds. It is inexpensive and works well with mould related materials. It can be manufactured at high quantities and is very durable and long lasting. It has been used for a large variety of health-related applications due to it being approved by the Food and Drug Administration
Question 1 Question Topic: A1 – Identification of Materials – Physical Characteristics Question: Given the Monomer Unit structure below answer the following: A: Name the plastic relating to it B: Write the density for both amorphous and crystalline (in g/cm^3) C: List 2 things commonly made with it. D: CALCULATE the molecular weight of polypropylene (g/mol) Answer: The plastic relating to the monomer structure above is Polypropylene. (PP) Polypropylene is one of the lower density fibers. The density for amorphous is 0.855 g/cm^3 and the density for crystalline is 0.946 g/cm^3. Polypropylene usually polymerizes by addition.
They have a relatively high level of hydrophilicity. Conversely, cationic surfactants such as cetyltrimethyl ammonium bromide (CTAB) release a positive charge in an aqueous solution. On the other hand, in alkali pH, amphoteric surfactants act as anionic while in acid pH, it act as cationic. Non-ionic surfactants such as partially hydrolyzed PVA (polyvinyl alcohol) have no charge (Li et al, 2008). Among four types of surfactants, partially hydrolyzed PVA is most frequent used because it gives the smallest microsheres (Jeffrey et al, 1991).
The synthesis of polymers is driven by dehydration reactions, which occurs when two monomers bond covalently and through this bonding, a water molecule is lost. Polymers can also be broken down into monomers through a reaction called hydrolysis. In this reaction, the bonds between monomers are broken through the addition of