The type of fiber used can be categorized into two main categories: The process of stretching ruptures a significant number of hydrogen bonds.
As stated earlier in the foundation of this unit, the only type of attraction that exists between molecules is Coulombic attraction between positive and negative charges. Figure 7 shows polymers of low molecular weight.
This is due to water molecules hydrolyzing a significant number of hydrogen bonds and in the process weakening the silk polymer.
Linearity Fiber polymer should be linear i. Action of water - The absorption of water molecules takes place in the amorphous regions of the fibre, where the water molecules compete with the free active side groups in the polymer system to form cross links with the fibroin chains.
Students who are watching can be Coulombic officers looking for violations of Coulombic attraction. Length of fibers is also a basis for classifying them into two groups staple and filament.
The astringent tannins in beverages like tea and coffee make this process more likely which could be why one rarely adds both milk and lemon juice to tea.
Dasgupta Hegde, et al. For stretch, ask student to equally stretch each material and visually observe which material stretches the farthest. This is often misinterpreted, in that the handle is regarded as a soft, because of the smooth, even and regular surface of silk filaments.
In groups, students visit a station and arrange the molecules obeying Coulombic attraction. With man-made fibers, the operation called drawing, which stretches the extruded and coagulated filament, causes the polymers to orient themselves longitudinally into a more or less parallel order, resulting in the formation of crystalline regions.
Types of Bonding based on Electronegativity In this activity, students will practice determining the type of bond made between atoms based on electronegativity differences.
This crystal-like structure gives cellulose low elasticity, leading to stretched-out fabrics after extensive wear. Either way, this or other posts on this site may be a useful Art Resource for you.
This planar structure leads to the smooth surface of silk. Ozone is a radical molecule.
Additionally, you can challenge students to bring in a piece of clothing that they particularly like for its texture.
Hydrogen bonding is strong, since it takes oC in order to break the hydrogen bonds in liquid water in order to produce steam which is composed of individual water molecules. Effect of alkalis - Alkaline solutions cause the silk filament to swell. It quickly found great use in pantyhose, brushes and bristles, fishing lines, and parachutes.
The competition can also be for the entire class and students could write down answers and check for the most correct at the end. Action of oxidizing agent - Silk fibre is highly sensitive to oxidizing agents.Intermolecular forces are repulsive at short distances and attractive at long distances (see the Lennard–Jones potential).
In a gas, the repulsive force chiefly has the effect of keeping two molecules from occupying the same volume. This gives a real gas a tendency to occupy a larger volume than an ideal gas at the same temperature and pressure.
Polymer solutions are considered quite good (monodisperse) when the variability or standard deviation of the molecular weight distribution is on the order of a couple of percent.
Sometimes, scientists use the polydispersity index  to describe the quality of a polymer solution. The orientation of polymers give rise to sufficiently effective inter-polymer forces of attraction to form a cohesive polymer system and, hence, a useful fiber.
The longer the polymers the more cohesive will be the polymer system and the stronger will be the fiber. Interparticle Forces: The forces of attraction between neighboring particles CHEM 1A Examples: BaSO 3 Strong IMFs alcohol, NH formaldehyde, MEK Weak IMFs Ionic Forces: whole charges attracting ions attracted to ions of the opposite charge the higher the charges, the stronger the attraction.
A textile is defined as a material that is made of interlacing fibers (thread or filament). A fiber is usually many polymers that are arranged and combined in a variety of bonding and non-bonding interactions. The method of interlacing fibers and the type of fiber used gives rise to the nearly endless variety of textiles available today.
Salt linkages, hydrogen bonds and Van der Waals' forces hold the polymer system of silk together. Since these inter-polymer forces of attraction are all hydrolyzed by the alkali, dissolution of the silk filament occurs readily in the alkaline solution.Download