Dibenzoate ester plasticizers

Benzoflex [Velsicol], TM for a series of plasticizers that are dibenzoate esters of dipropylene glycol or any of several polyethylene glycols. Use Primary plasticizer for vinyl resins adhesive formulations some grades in food-packaging adhesives. 

Fast-fusing plasticizers enable the PVC material to be processed faster or at lower temperatures. Generally it is in the area of plasfisol applications where the uses of faster fusing plasticizers are preferred. Examples of fast-fiising plasticizers include butyl benzyl phthalate (BBP), citrates, the epoxidized fatty acid plasticizer methyl epoxy stearate, alkyl sulfonic acid esters of phenol, dibutyl phthalates and tere-phthalates, and dibenzoate esters and benzoate ester blends. It should be noted that the use of BBP in PVC has rapidly declined because of product restrictions, while the use of dibutyl phthalate (DBP) declined in North America and in Europe years ago because of its high volatility. 

Most of the benzoate ester plasticizers are sold in blends. One of the top performing dibenzoate... 

Monobenzoate esters are prepared by the esterification of benzoic acid with one molar equivalent of alcohol, usually 2-ethylhexanol, isononanol, or isodecanol. Monobenzoates are not used as primary plasticizers but as secondary plasticizers where they help reduce plastisol viscosities, lower the fusion or processing temperatures, and give a boost to stain resistance in formulations based on GP plasticizers. Both mono and dibenzoate esters can be used in non-PVC materials such as acrylic films and caulks, latex coatings, polysulfide sealants and coatings, and polyurethanes. 

Plasticizers can be used to reduce both the viscosity and the cost of polyurethane and polysullide automotive and construction sealants. Higher molecular weight phthalate esters such as DINP, DIDP, and DUP or LI IP are generally suitable for most polyurethane sealant applications. Polysullide sealants require more polar plasticizers such as the alkyl benzyl phthalates, alkyl sulfonic acid esters, or dibenzoate esters. Recently the application of castor oil based plasticizers for polyurethanes has been described [46]. 

K-Flex dibenzoate esters are widely used as plasticizers for polyvinyl acetate emulsion systems. In these systems, K-Flex dibenzoate esters reduce set times, increase open time, increase film flexibility, reduce heat sealing tea eratures, and ia rove the dried film s resistance to oil, grease, and water. They also serve to enhance solution viscosities, often eliminating the need for other additives. K-Flex dibenzoate esters offer equal or superior performance to other recognized adhesive plasticizers. 

The bulk of this benzoic acid production capacity is consumed internally by the producers. Kalama and Chatterton convert over half of their production to phenol. A large portion of Velsicol s benzoic acid production is utilized in the manufacture of glycol dibenzoate plasticizer esters. 

Toxicological and carcinogenic aspects are very important for plasticizers destined to be used in toy manufacture but they are not known at this time for most of these plasticizers to ensure their safe use in this application. Presently known facts seem to indicate that some of the plasticizers may be potentially useful to replace phthalates. A report prepared for the European Commission Directorate-General Enterprise indicates a lower health risk with acetyl tributyl citrate, ATBC. It was also reported that the substitution of phthalates by benzoates (such as the diethylene glycol dibenzoate), alkylsulfonic phenyl esters, and possibly some adipates, trimellitates, sebacates and azelates should reduce health hazards however it is also recognized that the information available for DOA and ATBC is much less extensive than that available for phthalates. 

Benzoic acid esters, such as 1,3-propyleneglycol dibenzoate, are important plasticizers for polyurethanes. 

Citrates are fast-fusing plasticizers, especially when compared to many of the phthalate alternatives. Unfortunately citrates are not as permanent because of high volatility losses, and the finished PVC products do not remain as flexible for as long as those prepared from more permanent plasticizers. Citrates are often used in blends with the harder-to-process terephthalate or cyclohexanoate plasticizers, but in these applications, because of costs, dibenzoate plasticizers may be preferred. Citrate esters also find uses with other plastics such as acrylics, cellulosic polymers, and vinyl acetate. Acetylated tributyl citrate (ATBC) does have a number of food contact and medical approvals and is commonly found in toys, often in combination with DEHTP or DC9CH. 

Cushioned vinyl flooring is prepared by coating a substrate with various layers of plastisols. Traditionally these products used a mixture of plasticizers such as C7 to C9 phthalate esters, and are often found in blends with faster fusing plasticizers such as butyl benzyl phthalate (BBP) or dibenzoates. 

Monobenzoates and dibenzoates dominate the types of benzoates commercially available. The largest producer of benzoate esters is Velsicol Chemical Corporation their trade name is Benzoflex . Listed below are the various types of benzoate plasticizers manufactured by Velsicol ... 

Benzoflex S-358 triethylene glycol dibenzoate. This sohd ester is sold only in blends with other benzoate plasticizers. 

Benzoflex 352 1,4-cyclohexane dimethanol dibenzoate. This benzoate ester is a high-melting-point plasticizer that is compatible with PVC and is useful as a processing aid. 

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