Epoxidized vegetable oil and bio‐based materials as PVC plasticizer

Abstract

Phthalate esters received a considerable attention owing to its various applications and the harmful health effects resulting from phthalate exposure; thus, finding an alternative to phthalate derivatives became a necessity. Phthalate esters are commonly used as plasticizer in polymer formulation; in particular for poly(vinyl chloride) (PVC) formulation. According to the researches in the last 18 years, epoxidized vegetable oils are one of the alternatives that are strongly encouraged to substitute phthalate esters since they were proven to be valid in various applications, eco-friendly and sustainable resource. However, most of the production practices for epoxidized vegetable oil are via conventional epoxidation that concentrates on a catalyst that is homogeneous and non-reusable. This type of catalyst, however, causes several problems later in the process. Therefore, the selective epoxidation of vegetable oils process requires new catalytic systems that are more aligned with the green chemistry principles. This article reviews the harmful health effects associated with the exposure to phthalate esters products, explains the usage of oleochemicals resources as a substitute to phthalate esters and describes different approaches for the epoxidation of vegetable oils. Finally, it draws attention to the usage of epoxy and bio-based compounds as plasticizers in PVC manufacturing.

Synthesis and properties of castor oil based plasticizers

“…16 The T P1 values of PVC plasticized with ESO, ECO, EACO and EBCO were higher than those with DOTP, ACO and BCO, which proves that epoxy groups can absorb hydrogen chloride degraded by light and heat, preventing the continuous decomposition of PVC and prolonging the lifetime of PVC. 31,32 In addition, the T P2 values of PVC-ACO and PVC-BCO are lower than those of PVC-EACO and PVC-EBCO, which may be because the double bonds in ACO and BCO reduced the thermal stability. The char residue of PVC plasticized with DOTP is higher than that of the other plasticizers, indicating that ESO, ECO, ACO, EACO, BCO and EBCO could decrease the char residue of PVC blends more than DOTP.…”

Catalytic developments in the epoxidation of vegetable oils and the analysis methods of epoxidized products

“…Moreover, recent developments in the application of molybdenum-based catalysts for epoxidation have been reviewed as well. 99 When it comes to vegetable oils, ion exchange resin, 100 chemoenzymatic epoxidation, 101 and others associated with catalysts for epoxidation and properties of epoxidized vegetable oils 66,102,103 have been discussed in former review papers. As far as we know, the analytical methods for determination of conversion, selectivity, and epoxide yield have not been reported in the review paper.…”

The epoxidized linseed oil as a secondary plasticizer in PVC processing

“…[2,7,9] The modified vegetable oil such as epoxidized vegetable oil is a good candidate in accordance with this trend because it contains many epoxy groups and has renewable sources. [10][11][12] There are many types of epoxidized vegetable oils such as soybean oil [13][14][15] , rubber seed oil, etc. [16,17] that have been used as primary or secondary plasticizers for PVC.…”