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35-631: As head of Arvey Corp., Regenstein made many innovations in the paper, plastic and chemical fields. In 1931, Regenstein formed a business with his cousin, Julius Hyman, the Velsicol Chemical Corporation that manufactured several chlorinated insecticides including Dieldrin , Aldrin , Chlordane and Heptachlor which were the focus of Rachel Carson 's book Silent Spring . Regenstein and Hyman would later fall out when Hyman set up an independent business in Colorado to manufacture insecticides at

70-1018: A $ 30,000 penalty on Velsicol on August 31, 1978, for more than 300 violations of the NPDES permit which restricts the releases of pesticides endrin and more into sewage.   Endrin has minimal effect on soil, however from the Velsicol Chemical Corporation handbook, Endrin is “toxic to fish and wildlife” and it is recommended that Endrin is “kept out of lakes, streams and ponds”. Endrin is meant to be properly handled. The recommendations by Vesicol are “do not contaminate water”. In case fish kills, fish must be collected promptly and disposed of by buna”. According to InChem,”high toxicity of endrin can cause acute environmental problems when there are uncontrolled discharges during its manufacture, formulation or use.” InChem also recommends that “The manufacture, formulation, agricultural use, and disposal of endrin should be carefully managed to minimize contamination of

105-464: A United States activist is a stub . You can help Misplaced Pages by expanding it . This biographical article about a philanthropist is a stub . You can help Misplaced Pages by expanding it . Velsicol Chemical Corporation Velsicol Chemical Corporation is an American chemical company based in Rosemont, Illinois , that specializes in chemical intermediates for applications such as agrochemicals . It

140-471: A highly negative charge so that they repel each other. Polycarboxylate ether superplasticizer (PCE) or just polycarboxylate (PC), work differently from sulfonate-based superplasticizers, giving cement dispersion by steric stabilisation. This form of dispersion is more powerful in its effect and gives improved workability retention to the cementitious mix. Plasticizers can be added to wallboard stucco mixtures to improve workability. In order to reduce

175-501: A number of properties including improved workability and strength. The strength of concrete is inversely proportional to the amount of water added, i.e., the water-cement (w/c) ratio. In order to produce stronger concrete, less water is added (without "starving" the mix), which makes the concrete mixture less workable and difficult to mix, necessitating the use of plasticizers, water reducers, superplasticizers, fluidizer or dispersants. Plasticizers are also often used when pozzolanic ash

210-520: A polymer chain is more complex in the presence of plasticizer than what the Flory–Fox equation predicts for a simple polymer chain. The molecules of plasticizer take control over mobility of the chain - a polymer chain does not show an increase of the free volume around polymer ends. If plasticizer/water creates hydrogen bonds with hydrophilic parts of the polymer, the associated free volume can be decreased. The effect of plasticizers on elastic modulus

245-448: A retarding effect. Plasticizers are commonly manufactured from lignosulfonates , a by-product from the paper industry . Superplasticizers have generally been manufactured from sulfonated naphthalene condensate or sulfonated melamine formaldehyde , although newer products based on polycarboxylic ethers are now available. Traditional lignosulfonate-based plasticisers, naphthalene and melamine sulfonate-based superplasticisers disperse

280-585: A rubber formulation for a particular application. Plasticizers used in PVC and other plastics are often based on esters of polycarboxylic acids with linear or branched aliphatic alcohols of moderate chain length. These compounds are selected on the basis of many critieria including low toxicity, compatibility with the host material, nonvolatility, and expense. Phthalate esters of straight-chain and branched-chain alkyl alcohols meet these specifications and are common plasticizers. Ortho-phthalate esters have traditionally been

315-679: Is a solid organochlorine pesticide developed by Velsicol with the molecular formula of C 12 H 8 Cl 6 O {\textstyle {\ce {C12H8Cl6O}}} . The colorless and odorless crystalline solid is dissolved in a liquid for pesticide use against rodents, insects, and birds. The compound is widely regarded as an environmental hazard, showing acute toxicity in humans and severe toxicity in animals, specifically aquatic wildlife as well. Endrin can be exposed to humans by inhalation, skin absorption, or ingestion. There are many adverse health effects that are associated with Endrin. According to

350-440: Is added to concrete to improve strength. This method of mix proportioning is especially popular when producing high-strength concrete and fiber-reinforced concrete. Adding 1-2% plasticizer per unit weight of cement is usually sufficient. Adding an excessive amount of plasticizer will result in excessive segregation of concrete and is not advisable. Depending on the particular chemical used, use of too much plasticizer may result in

385-424: Is dependent on both temperature and plasticizer concentration. Below a certain concentration, referred to as the crossover concentration, a plasticizer can decrease the modulus of a material. The material's glass transition temperature will decrease, however, at all concentrations. In addition to a crossover concentration, a crossover temperature exists. Below the crossover temperature the plasticizer will also increase

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420-681: The Rocky Mountain Arsenal . Numerous lawsuits followed. Regenstein maintained an intense interest in the development of Chicago and its institutions. To honor him, the Joseph and Helen Regenstein Foundation, on November 9, 1965, gave $ 10,000,000 toward the new graduate research library at University of Chicago. His son Joseph Regenstein Jr was a life trustee of the university until his death on March 4, 1999, at age 75. This biographical article about

455-782: The 2017 volume was ~1.01 million metric tonnes and in Europe the figure was 1.35 million metric tonnes, split between various end-use applications with a chemical type trend moving to higher molecular weight (HMW) orthophthalates and alternative types following regulatory issues concerning lower molecular weight (LMW) orthophthalates. Almost 90% of polymer plasticizers, most commonly phthalate esters , are used in PVC , giving this material improved flexibility and durability. Other polymers which can contain high loadings of plasticizers include acrylates and cellulose -type plastics, such as cellulose acetate , nitrocellulose and cellulose acetate butyrate . It

490-507: The CDC, several studies have shown that people exposed to high levels of Endrin experience convulsions, jerking of legs and arms, twitching facial muscles, sudden collapse, or even death. Studies have also shown that animals who have eaten and breathed the same high levels of endrin had very similar health effects as humans. Although there are no long-term effects on human health directly linked to Endrin, its ability to create temporary illness caused

525-566: The core, preventing a stronger core. The sugars, chelating agents in lignosulfonates such as aldonic acids and extractive compounds are mainly responsible for set retardation. These low range water reducing dispersants are commonly manufactured from lignosulfonates , a by-product from the paper industry . High range superplasticizers (dispersants) have generally been manufactured from sulfonated naphthalene condensate, although polycarboxylic ethers represent more modern alternatives. Both of these high range water reducers are used at 1/2 to 1/3 of

560-426: The energy consumed drying wallboard, less water is added, which makes the gypsum mixture very unworkable and difficult to mix, necessitating the use of plasticizers, water reducers, or dispersants. Some studies also show that too much lignosulfonate dispersant could result in a set-retarding effect. Data showed that amorphous crystal formations occurred that detracted from the mechanical needle-like crystal interaction in

595-534: The environment, particularly surface waters. This United States manufacturing company–related article is a stub . You can help Misplaced Pages by expanding it . Plasticizer A plasticizer ( UK : plasticiser ) is a substance that is added to a material to make it softer and more flexible, to increase its plasticity , to decrease its viscosity , and/or to decrease friction during its handling in manufacture. Plasticizers are commonly added to polymers and plastics such as PVC , either to facilitate

630-647: The error was finally recognized, all the cattle in the state were culled. This error led directly to Gerald Ford 's half-hearted approval in 1976 of the Toxic Substances Control Act , which "remains one of the most controversial regulatory bills ever passed". The site of the St. Louis plant is one of the costliest Superfund sites in America. In 2014, the neighborhood around the plant was found to be contaminated with DDT, presumably by Velsicol decades before, prompting

665-422: The flocculated cement particles through a mechanism of electrostatic repulsion (see colloid ). In normal plasticisers, the active substances are adsorbed on to the cement particles, giving them a negative charge, which leads to repulsion between particles. Lignin , naphthalene, and melamine sulfonate superplasticisers are organic polymers. The long molecules wrap themselves around the cement particles, giving them

700-486: The gypsum particles, giving them a highly negative charge so that they repel each other. Energetic material pyrotechnic compositions , especially solid rocket propellants and smokeless powders for guns, often employ plasticizers to improve physical properties of the propellant binder or of the overall propellant, to provide a secondary fuel, and ideally, to improve specific energy yield (e.g. specific impulse , energy yield per gram of propellant, or similar indices) of

735-576: The handling of the raw material during fabrication, or to meet the demands of the end product's application. Plasticizers are especially key to the usability of polyvinyl chloride (PVC), the third most widely used plastic. In the absence of plasticizers, PVC is hard and brittle; with plasticizers, it is suitable for products such as vinyl siding , roofing , vinyl flooring , rain gutters , plumbing , and electric wire insulation/coating. Plasticizers are also often added to concrete formulations to make them more workable and fluid for pouring, thus allowing

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770-482: The lignosulfonate types. Traditional lignosulfonate and naphthalene sulfonate-based plasticisers disperse the flocculated gypsum particles through a mechanism of electrostatic repulsion (see Colloid ). In normal plasticisers, the active substances are adsorbed on to the gypsum particles, giving them a negative charge, which leads to repulsion between particles. Lignin and naphthalene sulfonate plasticizers are organic polymers. The long molecules wrap themselves around

805-549: The makeup of the smell do not find phthalates in appreciable amounts, likely due to their extremely low volatility and vapor pressure. Bio-based plasticizers have been investigated, such as glycerol triacetate (Triacetin) and acetyltributylcitrate . They are used in niche applications. Epoxidized soybean oil is used broadly as a secondary plasticizer in many vinyl applications. In the concrete technology, plasticizers and superplasticizers are also called high range water reducers. When added to concrete mixtures, they confer

840-536: The many elastomer applications such as tubing and hose products, flooring, wall-coverings, seals and gaskets, belts, wire and cable, and print rolls. Low to high polarity esters provide utility in a wide range of elastomers including nitrile , polychloroprene , EPDM , chlorinated polyethylene , and epichlorohydrin . Plasticizer-elastomer interaction is governed by many factors such as solubility parameter , molecular weight , and chemical structure. Compatibility and performance attributes are key factors in developing

875-708: The modulus. Over the last 60 years more than 30,000 different substances have been evaluated for their suitability as polymer plasticizers. Of these, only a small number – approximately 50 – are today in commercial use. Ester plasticizers are selected based upon cost-performance evaluation. The rubber compounder must evaluate ester plasticizers for compatibility, processibility, permanence and other performance properties. The wide variety of ester chemistries that are in production include sebacates , adipates , terephthalates , dibenzoates , glutarates , phthalates , azelates , and other specialty blends. This broad product line provides an array of performance benefits required for

910-447: The most dominant plasticizers, but regulatory concerns have led to the move away from classified substances to non-classified which includes high molecular weight ortho-phthalates and other plasticisers, especially in Europe. Antiplasticizers are polymer additives that have effect opposite to those of plasticizers. They increase the modulus while decreasing the glass transition temperature. Substantial concerns have been expressed over

945-428: The propellant. An energetic plasticizer improves the physical properties of an energetic material while also increasing its specific energy yield. Energetic plasticizers are usually preferred to non-energetic plasticizers, especially for solid rocket propellants . Energetic plasticizers reduce the required mass of propellant, enabling a rocket vehicle to carry more payload or reach higher velocities than would otherwise be

980-474: The reasons that were given for the dismissal were found to be substantiated. For years, Velsicol produced polybrominated biphenyls , DDT , cattle feed additives, and various other chemicals at its Michigan Chemical Corporation plant in St. Louis, Michigan . In 1973, a packaging error at the plant resulted in several thousand pounds of PBBs contaminating cattle feed which was later fed to animals across Michigan. When

1015-440: The removal and replacement of soil at 96 residential properties. In 2005, Velsicol was acquired by the private equity firm Arsenal Capital Partners , who, in 2007, re-branded the unit manufacturing benzoic acid , sodium benzoate , and specialty plasticizers as Genovique Specialties Corporation . Arsenal still owns Velsicol. They began selling benzoic acid and sodium benzoate again in 2015 and 2017 respectively. Endrin

1050-448: The safety of some polymer plasticizers, especially because some low molecular weight ortho-phthalates have been classified as potential endocrine disruptors with some developmental toxicity reported. Plasticizers can escape plastics due to migration and abrasion of the plastic since they are not bound to the polymer matrix. The " new car smell " is often attributed to plasticizers or their degradation products, however, multiple studies on

1085-488: The substance to be banned from being used as an insecticide and eventually the production of Endrin altogether within the United States. Because of the potentially harmful adverse effects of Endrin on human health and wildlife, the chemical was officially banned on October 10, 1984. However production of Endrin wasn’t canceled until 1991 in the United States. United states vs. Velsicol Chemical Corp. The civil court imposed

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1120-421: The water contents to be reduced. Similarly, they are often added to clays , stucco , solid rocket fuel , and other pastes prior to molding and forming. For these applications, plasticizers largely overlap with dispersants . Plasticizers for polymers are either liquids with low volatility or solids. According to 2017 data, the total global market for plasticizers was 7.5 million metric tonnes. In North America

1155-405: Was commonly thought that plasticizers work by embedding themselves between the chains of polymers , spacing them apart (increasing the "free volume"), or swelling them and thus significantly lowering the glass transition temperature for the plastic and making it softer. It was later shown that the free volume explanation could not account for all of the effects of plasticization. The mobility of

1190-458: Was founded in 1931 by Joseph Regenstein and Julius Hyman. When, in 1962, the landmark anti- pesticide book Silent Spring was first published, Velsicol was the sole manufacturer of two pesticides – chlordane and heptachlor  – featured prominently within it. Subsequently, these pesticides were banned. At the time, Velsicol threatened legal action against Silent Spring' s publisher Houghton Mifflin , though ultimately no such action

1225-483: Was taken. In 1979, Australian politician and medical researcher John Coulter gave a lecture that mentioned how Velsicol had handled information about the cancer-causing properties of the two pesticides. Velsicol contacted the director of the Institute of Medical and Veterinary Science (now SA Pathology ), where Coulter worked, about the lecture. Coulter lost his job in early 1980. In a later court hearing, however, none of

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