Production overview of several unused environmentally friendly plasticizers and plasticizers

(1) Citrate Commonly used citrate plasticizers, there are two main varieties: tributyl citrate, acetyl tributyl citrate

Tributyl citrate is obtained by direct esterification of citric acid and butanol. Acetyl tributyl citrate can be obtained by reacting tributyl citrate with ester acid, both of which are colorless and transparent oily liquids, non-toxic and mildew-proof. Can be used for food packaging materials. It is often used in polyvinyl chloride and various fiber resins.

(2) Benzoic acid ester Due to the development of petrochemical industry, polytoluene raw materials are provided, and environmentally friendly plasticizers oxidize them to obtain benzoic acid, which is then Dehydration gives anhydrides. Benzoic acid and its anhydrides are esterified with alcohols to obtain benzene polyesters.

For example, if R=C8H17, it is tri-n-octyl trimellitate (TOTM), and if R=C10H21, it is tri-n-decyl trimellitate.

They are colorless to pale yellow viscous oily liquids with excellent heat resistance and durability, and good compatibility and low temperature resistance. Outstanding electrical insulation properties. It has attracted much attention in recent years.

(3) There are generally two types of pentaerythritol esters:

The ether type is formed by the esterification of dipentaerythritol and C5~C7 fatty acids under the catalysis of sulfuric acid. The ester type is formed by the esterification of pentaerythritol, adipic acid, and fatty acid under the catalysis of sulfuric acid. Both are pale yellow viscous oily liquids. Commonly used in polyvinyl chloride, it is a heat-resistant, aging-resistant, and extraction-resistant plasticizer. It has low volatility and good electrical properties, but poor low temperature resistance.

(4) Amide plasticizers Representative varieties of this kind of plasticizers such as dibutyl oleamide (DBO), about the properties of various plasticizers See table for usage.

1. Production overview of plasticizer

Due to the large amount of plasticizers used and the variety of varieties, the current production technology of plasticizers tends to develop in two aspects: one is the main plasticizer Continuous large-scale production, such as the consumption of phthalate plasticizers accounted for about 80% of the total plasticizers, the production volume is very large, so new plasticizers appeared with dioctyl phthalate as the main The continuous mass production of the center. At present, it generally reaches the level of single-line production capacity of 2 to 50,000 t/a. The production capacity of a set of DOP continuous production equipment of BASF has reached 100,000 t/s. The biggest advantage of large-scale continuous production is economy.

On the other hand, since there are many types of plasticizers, and the production volume of one type is often small, in order to adapt to the multi-variety and small batches of other plasticizers Production, mostly using general-purpose equipment for intermittent production. That is the so-called “universal” production device, and a set of production device of Reichold Chemical Inc. in the United States is a typical example of this “universal” production device. The device can usually process more than 60 kinds of raw materials. It has 13 raw material storage tanks with separate pipes and 24 finished product receiving tanks. The volume of the reactor is 18 square meters and the production capacity is 13,000 to 16,000 t/a. At the same time, it has neutralizer (10m³), static device (2X380m³), scrubber, filter, stripper and other auxiliary equipment corresponding to the volume of the reactor. Can produce phthalate, adipate, azelate, sebacate, US

About 30~40 kinds of maleate, fumarate, trimellitate, epoxy compound, polyester and some other plasticizers , which is equivalent to 95% of the commonly used plasticizers in the United States.