Hydraulic fracturing of chemicals are used per fracturing. A typical fracture treatment uses between 3 and 12 additive chemicals. Although there may be unconventional fracturing fluids, typical chemical additives can include one or more of the following: The most common chemical used for hydraulic fracturing in the United States in 2005–2009 was methanol, while some other most widely used chemicals were isopropyl alcohol, 2-butoxyethanol, and ethylene glycol. Typical fluid types are: For slickwater fluids the use of sweeps is common. Sweeps are temporary reductions in the proppant concentration, which help ensure that the well is not overwhelmed with proppant. As the fracturing
Memory foam memory foam, companies began using open cell structure to improve breathability. In 2006, the third generation of memory foam was introduced. Gel visco or gel memory foam consists of gel particles fused with visco foam to reduce trapped body heat, speed up spring back time and help the mattress feel softer. This technology was originally developed and patented by Peterson Chemical Technology, and gel mattresses became popular with the release of Serta's iComfort line and Simmons' Beautyrest line in 2011. Gel-infused memory foam was next developed with what were described as "beads" containing the gel which, as a phase-change material,