Styrofoam cups, polystyrene

The experiment will require a balance to determine the mass of a sample and possibly a pipet to measure a volume, from which a mass may be calculated using the density. A calorimeter, usually a polystyrene (Styrofoam) cup, is needed to contain the reaction. Finally, a thermometer is required. Tables of heat capacities or specific heats may be provided. 

Polymers are giant molecules made by combining many smaller molecules. Some polymer molecules may contain several million atoms. Important natural polymers include natural rubber, starch, and DNA. Rubber bands and some automobile tires are made of natural rubber. Starch is found in many foods. DNA is the molecule of heredity. Some important polymers made by scientists are nylon, which is used in making fabrics, polyethylene, which is used to make plastic bags and plastic bottles, and polystyrene, which is used in making styrofoam cups and insulation. 

Napalm B was developed by Dow Chemical during the Vietnam War as a replacement for the original napalm jelly in firebombs. It is stickier and burns much hotter than the original filler. The Dow formula used 25 percent gasoline, 25 percent benzine, and 50 percent polystyrene. Polystyrene is a common plastic used for such diverse items as toys, styrofoam cups, and packing-filler "peanuts." As anyone who has tried to spray-paint a styrofoam cooler knows, polystyrene dissolves into a sticky mush when it comes in contact with hydrocarbons such as paint or gasoline. It is this quality of polystyrene that makes napalm B so effective for molotov cocktails. 

Any form of polystyrene will work, but more solid forms take longer to dissolve. Styrofoam cups or packing peanuts dissolve faster because of their lower densities. Unfortunately, the air pockets in their structure take up space, which means that it takes a lot longer to produce. 

Constant-Pressure Reaction Calorimeters. A constant-pressure calorimeter measures the change in enthalpy AH for a chemical reaction occurring in solution under constant atmospheric pressure a trivial example is the coffee-cup calorimeter, which is constructed from two nested polystyrene (Styrofoam ) cups having holes through which a thermometer and a stirring rod can be inserted. The inner cup holds the solution in which the reaction occurs, while the outer cup provides insulation. (A fancier version uses a Dewar181 vessel to approximate adiabatic conditions for the reaction.) Then... 

Only about 5 percent of a styrofoam cup is polystyrene. The rest is air. 

PS Polystyrene Styrofoam cups, egg cartons, disposable utensils, packaging materials, appliances Molded items such as cafeteria trays, rulers, Frisbees , trash cans, videocasettes... 

Styrofoam cups, takeout containers, shipping, and packaging Expandable polystyrene HBCD NA Innes and Innes (2003)... 

Student Annotation Styrofoam is a registered trademark of the Dow Chemical Company. It refers specifically to extruded polystyrene used for insulation in home construction. "Styrofoam" cups, coolers, and packing peanuts are not really made of Styrofoam. 

You yearn for the old days of polystyrene (Styrofoam) cups, which never got hot. Being an ambitious student (and looking for a distraction), you decide to come up with a process to recycle polystyrene (Styrofoam) so that environmental concerns will no longer keep the coffee shop from using this very good insulating material. 

The annual production of styrene in the United States is approximately 1 2 X 10 lb with about 65% of this output used to prepare polystyrene plastics and films Styrofoam coffee cups are made from polystyrene Polystyrene can also be produced m a form that IS very strong and impact resistant and is used widely m luggage television and radio cabinets and furniture... 

Polystyrene is a common polymer used to make Styrofoam containers, packing peanuts, and insulation. Another kind of packing peanut used is made of starch. Place about a cup of acetone in a glass container. Acetone is available wherever paint is sold. Do this in a well-ventilated area. Be careful with the acetone, it can remove paint and ruin finishes. Add a starch packing peanut to the acetone and then a Styrofoam packing peanut. The starch peanut will not dissolve, but the polystyrene peanut will. Dilute the acetone with ample amounts of water before disposing down the sink. 

Figure 12.29 shows that using styrene as the monomer yields polystyrene. Transparent plastic cups are made of polystyrene, as are thousands of other household items. Blowing gas into liquid polystyrene generates Styrofoam, widely used for coffee cups, packing material, and insulation. 

PS (polystyrene) Styrofoam, used in take-out containers, meat and bakery trays, and, in its hard form, clear take-out containers and some plastic cutlery and cups Avoid it leaches chemicals into food, some of which can disrupt normal hormonal functioning. 

PS Polystyrene (Styrofoam) Hot-beverage cups, fast-food clamshell containers, egg cartons, meat trays... 

H H / C=C / H Styrene /H H 1 1 d-c—c— rO Polystyrene / n foam insulation and packing (Styrofoam ), plastic utensils, rigid, transparent salad containers, clothes hangers, foam cups, and plates... 

CH2=CHCeH5 (styrene) [CH CH (C6H5)] Polystyrene, PS Jugs, cups, packaging, styrofoam, appliance parts... 

Polystyrene (10.8) A thermoplastic polymer made from styrene monomer used in plastic model kits and plastic cutlery. Can be aerated to produce a foam (Styrofoam ) and made into coffee cups or insulated food containers. 

Styrene can also be homopolymerized to produce polystyrene (Sec. 22.2). This material is one of the most versatile plastics ever invented. For example, it can be molded into rigid cases for radios and batteries or formulated in a more flexible form useful in the manufacture of toys and all kinds of containers. Polystyrene can also be produced in the form of a lightweight foam known as Styrofoam . This foam is used for insulation in buildings and is molded into ice chests and disposable cups for hot and cold drinks. 

Styrene is the monomer used to make polystyrene, which has a multitude of uses, the most common of which are in packaging and insulated Styrofoam beverage cups. Styrene is produced by the dehydrogenation of ethylbenzene. Ethylbenzene is formed by reacting ethylene and benzene. There is very little ethylbenzene sold commercially, because most ethylbenzene manufacturers convert it directly into styrene. 

In 2000, 3 million tons of polystyrene, commonly known as Styrofoam, was made for use in disposable coffee cups and food packaging, and 2.3 million tons was thrown away. Polystyrene waste does not break down quickly and is difficult to recycle. A new strategy based on the recycling of Styrofoam into PHA was developed by a team of microbiologists at University College Dublin [15]. These scientists found that a soil bacterium, based on Pseudomonas putida, thrives on dirty styrene oil (CgHg) derived from the pyrolysis of polystyrene. In this type of reaction, the styrene is the somce of carbon, which is then stored as PHA (Figure 8.17). 

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