What comes to mind when you think of Plastic? Tupperware? Cheap toys from china? Plastic Bags I don’t blame you but what if I were to say cornflakes? Or woolly jumpers? Or an antique oak wardrobe? It may be hard to believe but all these things are made of Polymers. Polymers are chemical compounds deprived of long repeating chains of monomers. The first recorded discovery of polymers dates back to ancient Myan civilizations in the 1500s as their children were found playing with balls made from local rubber trees. However it was only until 1907 that Leo Bakeland fabricated the first synthetic plastic Bakelilte, Leo would later go on to be call "The Father of the Plastics Industry"[6]. Polymers have had significant effect on the way we lead our …show more content…
Additionally, PS is non-toxic and odorless and used in the food packaging …show more content…
Aromatic molecules are very stable, and do not break apart easily to react with other substances. Whilst polypropylene is an aliphatic polymer; most aliphatic compounds are flammable. Furthermore, the melting point, in regards to polymers focuses not on a solid–liquid phase transition but a transition from a crystalline or semi-crystalline phase to a solid amorphous phase. Measures the strength of molecular bond and indicates how much energy is required to break these bonds. The melting point for Polypropylene is 130°C whilst the melting point for Polystyrene 210-249 °C. Due to a higher boiling point more heat energy is required to break polystyrene bonds. Overall it seems that polystyrene has better strength than polypropylene. Conclusion Since their discovery in the 1500s polymers have come a long way and are required in our lives. Throughout this article decisions upon which is the best polymer were made using the earlier criteria of versatility; Environmental impact and strength. As a result of the criteria it can be seen that … is the best
Fire and thermal properties of PA 66 resin treated with poly-N- aniline- phenyl phosphamide as a flame retardant
• Lowering freight costs because of the light weight of plastics. • Plastics can be shaped and made in different patterns hence advantageous for marketing and shipping. • Plastics are made from natural resources such as
Have you ever wondered why the plastic bag that you left on the porch during winter cracks or breaks more easily than when you left it during summer time but a piece of wood which was left just like the plastic bag has no effect whatsoever? This is because of a phenomenon, which only happens to polymers, known as the glass transition. For each polymer, there is a certain temperature at which the amorphous polymers undergo a second order phase transition from a rubbery and viscous amorphous solid to a brittle and glassy amorphous solid called the glass transition temperature, Tg.1 When the polymer, or in this case, the plastic bag, is cooled below their glass transition temperature, it becomes hard and brittle like a glass but when it is used above their glass transition temperatures, it might have a different effect than when used at room temperature or below the glass transition temperature as normally, different types of polymers like clothes, food packaging, insulations for wires, etc. are either used above their glass transition temperatures or
In the early morning hours of January 12th 1981, twenty-five detonations were heard coming from the ramp at Muñiz Air National Guard Base, located in the Luis Muñoz Marín International Airport in San Juan, Puerto Rico (PR). It was a terrorist attack. The result? Ten A-7D aircrafts and a single F-104 destroyed, with a total of $45,000,000 in damages. It was the largest attack on the US military since the Vietnam War. The culprits? All members of a separatist domestic terrorist group called Ejercito Popular Boricua (English: Boricua Popular Army or BPA, EPB) more commonly known as Los Macheteros (“The Machete Wielders”); a nickname that conjures images of the improvised group of Puerto Ricans that banded together to defend and fight the United States Army when they invaded during the Spanish-American War. BPA’s main ideology is a free Puerto Rico, free from the colonial status that United States has on PR, and for PR to become its own sovereign state. Although BPA is not as active as it once was, they still promote and will fight for PR’s independence. But to understand the history and origins, ideologies, and goals of BPA we must go back in time to recognize why such a group even exists.
A group of polymer chains can be organised together in a fiber. How the polymer chains are put together is important, as it improves the properties of the material. The flexibility, strength and stiffness of Kevlar fiber, is dependent on the orientation of the polymer chains. Kevlar fiber is an arrangement of molecules, orientated parallel to each other. This orderly, untangled arrangement of molecules is described as a “Crystalline Structure”. A manufacturing process known as ‘Spinning’ is needed to achieve this Crystallinity structure. Spinning is a process that involves forcing the liquefied polymer solution through a ‘die’ (small holes).
The popular teen movie “Mean Girls” accurately portrays several concepts from Chapter Two including Interaction Appearance Theory and Undue Influence, just to name a few that allow teen viewers to see the type of communication there is or will be in high school. Through the interactions with her new peers, Cady Heron is able to communicate and experience several of the concepts learned in Chapter Two thanks to the interactions she had with the deceiving Regina George.
With the uproar over BPA and all the bad press it has been receiving there are those out there who believe that there is no issue concerning BPA. Some scientists have had problems recreating similar results from the experiments done by early researchers. Even the FDA and toxicologist scientists have worked together to study and understand the chemical compound with no results of it being harmful or deadly. The plastic industry has revolutionized our world when it comes to how we depend on their products in our everyday lives, but ...
The most common form of polyethylene is petroleum based or olefins based; as before mentioned polyethylene compounds have a wide commercial applicability and are made from non-renewable resources (Harding, Dennis, von Blottnitz, Harrison, & S.T.L., 2007). Its manufacturing processes are regarded as energy intensive and release significant amount of CO2 and heat into the atmosphere (Broderick, 2008). Next a little more detailed description of polyethylene’s production processes will be presented, with a focus on the way the material inputs are extracted and synthesized.
According to the American Council of Chemistry, plastics, which are otherwise known as polymers, are comprised of carbon, hydrogen, chlorine, nitrogen, sulfur, oxygen, and other elements that are combined through the conversion of natural products like oil, natural gas, or coal (ACA, n.d.). Between 7 and 8 % of the oil and natural gasses produced annually are used either directly in the conversion of such fossil fuels to plastics, or in powering the processes to produce plastics (Hopewell, Dvorak & Kosior, 2009). Plastic combinations can either form as thermoplastics, which are plastics whose atoms are connected in long chains that can be melted and reused, or thermosets, which are plastics whose atoms are arranged in three dimensional patterns that cannot be melted or reused (ACC, n.d.). Plastics are used in a wide range of products. For example, polyesters are used in textiles and fabrics, polyvinylidene chlorides are used for food packaging, polycarbonates are used for glasses and disks, and more. By the United States energy averages of 2015, each kg of plastic produced requires 62-108 mega joules of energy. The plastic requiring the largest amount of energy per kg is silicon which required about 235 mega joules of energy per kg. Three hundred and twenty two million metric tons of plastic produced in 2015 alone, and that value continues to raise, (Global plastic production,
Polyethylene (PE) is one of the most commonly used polymers which can be identified into two plastic identification codes: 2 for high-density polyethylene (HDPE) and 4 for low density polyethylene (LDPE). Polyethylene is sometimes called polyethene or polythene and is produced by an addition polymerisation reaction. The chemical formula for polyethylene is –(CH2-CH2)n– for both HDPE and LDPE. The formation of the polyethylene chain is created with the monomer ethylene (CH2=CH2).
The purpose of this experiment was to create a polymer by reacting a mixture of decanedioyl dichloride and dichloromethane with a mixture of water, 1,6-hexadiamine and sodium carbonate. Specifically, we created the polymer Nylon-6,10. Nylon-6,10 polymers are used in a vast majority of things we use in everyday life such as zippers, the bristles in brushes, and even car parts. This experiment was different from the industrial method of making nylon because that takes place at a much higher temperature. A polymer is a substance that has a structure made of similar or identical units bonded together. All polymerizations fall into two categories: step-growth and chain-growth (both of which we used to form our polymer). Step growth polymerization
Polymer-Polyethylene is partially crystalline as well as amorphous because it has crystalline and amorphous regions. Also it has linear chains so this is the simplest structure compared to a branched or network chain. This can be of an advantage to it over other types of materials as its good toughness and elongation makes it very significant in the engineering industry as it can be moulded or extruded into shape...
Although plastics have had a remarkable impact on our culture and lifestyle, the production and use of plastics pose increasing threat to environment. Most plastics are made from fossil fuels and thus plastics production has an impact on oil consumption, both as a raw material and to deliver energy for the manufacturing process (van der Voet et al, 2003). The proce...
The plastics industry has developed significantly since the invention of various methods for the manufacture of polymers. Plastic has several essential advantages, such as light weight, durability, an available cost relative to many other materials and an ability to be easily transformed (Andrady, and Neal, 2009). Plastics contribute to the safety of consumers’ food and water packaging usage as well as their health. Water has become an essential issue in urban areas, whereas the mechanism for the storage and supply of clean drinking is provided by plastics (Thompson, Moore, vom Saal, and Swan, 2009). In addition, plastic can be easily manufactured, and it is established in a range of various water distribution and control systems; for example, land drainage, storm water, irrigation and sewerage. Plastic food packaging usually provides secure, time-dependent storage of the products by using atmosphere and temperature control inside the package as well as using oxygen scavenger technology and using gas-flush packaging (Andrady, and Neal, 2009). That is why plastics are progressively more used in many areas; for example, in packaging, transportation, medicine, sport, agriculture, electronics, building and construction. This shows that plastic has become a widely-used building material of a significant number of
My main aim during my undergraduate studies was to get an overview of the various fields in chemical engineering and identify a field of interest in which I could pursue my research career. Because of their vast applications, Materials & Polymer Sciences, in general, have attracted m...