WO2012174620A1

WO2012174620A1 - Phthalate-free primary-plasticizer composition, method for producing same and uses thereof

Info

Publication number: WO2012174620A1
Application number: PCT/BR2012/000176
Authority: WO
Inventors: Massayochi Mário HOCIKO
Original assignee: Kekapar Administração E Participações S/A.
Priority date: 2011-06-22
Filing date: 2012-06-11
Publication date: 2012-12-27
Also published as: AR086706A1; BRPI1102794A2; UY34151A

Abstract

The present invention aims to provide phthalate-free plasticizer compositions containing plant oil monoacetate as the main component, which can be used for processing halogen-containing polymers, preferably polyvinyl chloride, to improve the processability of same. A first embodiment of the invention relates to a plasticizer composition comprising plant oil derivatives, said derivatives being products of the esterification of epoxidized plant oils, mainly epoxidized plant oil monoacetates. A second embodiment of the invention relates to a method for producing a plasticizer containing epoxidized plant oil monoacetate as the main component, said method comprising the reaction between epoxidized plant oil, or a mixture of epoxidized plant oils, and glycerin triacetate, which are present in the reaction mass in a molar ratio ranging from about 2:1 to 4:1. In a third embodiment, the invention relates to the use of the phthalate-free plasticizer composition for preparing strands, cables or footwear.

Description

COMPOSITION OF PRIMARY PLASTIFICANTS FREE OF FTALATES, OBTAINING PROCESS AND ITS USES

Field of the Invention

The present invention relates to phthalate-free primary (or main) plasticizers. More particularly, the plasticizers of the invention are plasticizing compositions of epoxidized vegetable oil monoacetates and / or diacetates used in vinyl chloride (PVC) polymers to reduce their high stiffness. Foundations of the Invention

In the processing of halogen-containing organic plastics, more particularly polyvinyl chloride (PVC), in general, additives are incorporated into such plastics with the intention of conferring certain functions on the resulting product. Such additives may have the function of developing certain effects during plastic processing or may result in certain properties conferred to the obtained products. Plasticizers are an example of additives incorporated into thermoplastic polymers. Plasticizers are substances that improve the processability of finished products, reducing system viscosity and increasing the mobility of macromolecules. In physicochemical terms, plasticizers cause Tg to shift to lower temperatures. The polymer that accepts the highest concentration of plasticizer is PVC.

Basically, the action of plasticizer is to decrease the binding intensity between the polymer molecules. These Bonds (known as Van der Walls forces) can give the polymer, for example, PVC, an extremely high stiffness. The plasticizer decreases these forces, reducing intermolecular attraction and thereby increasing the flexibility of the polymer chain and causing interference with processing conditions and end product properties such as hardness, Vicat softening temperature, flexibility, etc.

The main characteristics of a suitable plasticizer are: purity; compatibility in the processing of thermoplastic mass; high permanence index, ie low migration; low toxicity, improvement of properties conferred to the polymer as a function of its content in the mixture; no color, ie no change in polymer color; heat and light stability; resistance to leaching (water extraction) and to be tasteless and odorless.

Plasticizers are widely used in improving the processability of thermoplastic polymers. The types of plasticizers commonly used are: phthalic acid esters (phthalates), trimethylates, epoxy and polymeric (linear thermoplastic polyesters). Phthalates, for example dioctyl phthalate (DOP), diisononyl phthalate (DINP), diisobutyl phthalate (DIBP), diisodecyl phthalate (DIDP) are the cheapest and therefore the most widely used.

Despite the frequent use of traditional plasticizers, such as PDO, there are reports of problems related to human health or the environment. In particular, phthalates are biocumulative and are introduced into the environment through the leaching process. In this sense, Several solutions have been proposed to obtain a plasticizer with good properties, especially for PVC polymers, and which do not present the problems of traditional plasticizers. BRPI0705276 describes compounds of ethyl and / or isoamyl esters of fatty acids from vegetable oils as primary PVC plasticizers. These compounds are obtained from the transesterification reaction of at least one type of vegetable oil with ethanol or isoamyl alcohol and subsequent epoxidation. The resulting plasticizers have an oxiranic index of 8 or less.

Document BRPI0705621 discloses epoxidized bioesters obtained by partial transesterification of vegetable oils with ethyl alcohol or glycerin, followed by acetylation and epoxidation, resulting in primary plasticizers for PVC with oxiranic index equal to or less than 8.

BRPI0802148 describes a plasticizer composition obtained from vegetable oils comprising a compound of formula R1-0-R2 obtained by a process consisting of the steps of: (1) methanol and / or ethanol interesterification of mono-, di- and triglycerides present in vegetable oils with an iodine index greater than 100; (2) interesterification of the ethyl and / or methyl esters thus obtained with cyclohexanol and (3) epoxidation of the cyclohexyl esters thus obtained, where RI corresponds to the acyl portion of the mono-, di- and triglycerides of the vegetable oils with index of iodine greater than 100, epoxidized in its unsaturation and R2 corresponds to the cyclohexyl radical. The fact that unmodified vegetable oils are widely incompatible with PVC resin is known, however, certain modifications of vegetable oils, such as soybean oil epoxidation, make these compounds compatible with PVC resin. Thus, epoxidized soybean oil has been used as a secondary PVC plasticizer. In other words, there is still a need for the presence of a conventional primary plasticizer such as those of the phthalate type. The poor compatibility of partially esterified and epoxidized soybean oil with PVC resin has been attributed to the low solubility of partially epoxidized soybean oil in said resin and to the polarity difference between plasticizer and resin. Thus, in order to be able to replace phthalates with modified vegetable oils for use as primary plasticizers, a commitment to improve the compatibility between plasticizer and resin and to maintain the thermal stabilization properties of modified vegetable oils must be met.

In US6797753 it is proposed to increase the amount of vegetable oil derived plasticizer to be incorporated into the PVC resin in a concentration above 15%, for example up to about 70%, making such vegetable oil derivative a primary plasticizer. To achieve this objective, combinations of substantially completely esterified and epoxidized fatty acids derived from commonly available vegetable oil derived fatty acids are provided herein. To this end, a process is employed comprising (1) the creation of ester bonds by linking fatty acids derived from vegetable oils (e.g. oleic, linoleic, palmitic acids) to monoalcohols or polyalcohols by direct esterification and (2) epoxidation of such esterified products (containing saturated or unsaturated fatty acids) to increase the polarity and compatibility of these PVC resin reaction products .

State-of-the-art proposals for making primary plasticizing PVC vegetable oil derivatives do not fully meet this objective. Such proposals have disadvantages related either to effects that are harmful to man or the environment or to unsatisfactory product properties for their intended use given the wide range of uses such as hoses, shoe soles and food packaging. The present invention discloses a plasticizer composition containing as a major component phthalate-free vegetable oil monoacetate.

Summary of the Invention

The present invention aims to provide plasticizing compositions containing as a major component phthalate-free vegetable oil monoacetate for use in processing halogen-containing polymers, preferably polyvinyl chloride, to improve their processability.

A first embodiment of the invention relates to a plasticizer composition comprising vegetable oil derivatives, said derivatives being esterified products of epoxidized vegetable oils, mostly epoxidized vegetable oil monoacetates. Preferably, the compositions of the invention have an oxiranic index in the range of 5.0 to 5.8%, and an acidity index in the range of 0.3 to 0.6 mg / g of sample.

A second embodiment of the invention relates to a process for obtaining a plasticizer containing as a major component epoxidized vegetable oil monoacetate, said process comprising reacting epoxidized vegetable oil, or mixing epoxidized vegetable oils with glycerine triacetate present in reaction mass in a molar ratio in the range from about 2: 1 to 4: 1. The resulting product need not necessarily be homogeneous in the sense of a single molecular structure. Indeed, said product is preferably a more or less complex mixture of different epoxidized vegetable oil esters, preferably having the epoxidized vegetable oil monoacetate as the major component.

In a third embodiment, the invention relates to the use of the phthalate-free plasticizer composition for the preparation of yarns, cables or shoes. Brief Description of the Drawings

Figure 1 presents a graph showing the specific rupture strain (%) of PVC compositions containing 100 PCR (Parts per Hundred Resin), 80 PCR, 60 PCR and 40 PCR of the plasticizer of the XYK invention. Figure 2 presents a graph showing the maximum voltage

(Kgf / mm ² ) of PVC compositions containing 100 PCR (Parts per Hundred Resin), 80 PCR, 60 PCR and 40 PCR of the plasticizer of the XYK invention. Detailed Description of the Invention

The process according to the invention is a transesterification reaction of glycerine triacetate epoxidized vegetable oil esters, preferably in the presence of an appropriate catalyst, and in the transesterification reaction the oxirane rings (epoxide groups) of the vegetable oil esters epoxidized remain intact. Transesterification is carried out at a temperature in the range of 50 to 180 ° C, preferably in the range of 60 to 150 ° C, and more preferably in the range of 75 to 130 ° C, and for a period of time ranging from 1 hour to 5 ° C. hours, more preferably ranging from 1.5 hours to 3 hours, further stirring the reaction mass at a speed in the range of 80 to 250 rpm, more preferably in the range of 100 to 200 rpm.

The transesterification catalysts used in the present invention are known from the prior art and may be selected from the group consisting of basic compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium methoxide, sodium ethylate; or tin (IV) compounds such as dibutyl tin butyrate. Preferred catalysts of the process of the invention are sodium methoxide and sodium hydroxide. The amounts of catalyst used in the process of the invention are preferably in the range 0.05 to 1.0% (w / w), more preferably in the range 0.1 to 0.5% based on the total amount of epoxidized vegetable oil esters and glycerine triacetate used.

The epoxidized vegetable oil esters preferably used in the process of the present invention are epoxidized esters. fatty acids and monohydroxyl alcohols, and in said epoxidized vegetable oil esters, the epoxidized fatty acid moiety is selected from the group consisting of soybean oil epoxide, flaxseed oil epoxide, sunflower oil epoxide, epoxide rapeseed oil, castor oil epoxide, canola oil epoxide, palm oil epoxide, peanut oil epoxide and other appropriate vegetable oil epoxides. Those skilled in the art know the meaning of the term "monohydroxyl alcohols" as used herein and no further definition is required. In a preferred embodiment of the invention a mixture of epoxidized vegetable oils may be used for transesterification with glycerine triacetate.

The molar ratio between the epoxidized vegetable oil ester glycerine triacetate reagents according to the invention is preferably adjusted to values in the range of 2: 1 to 4: 1. When the ratio of epoxidized vegetable oil esters to glycerine triacetate is in the range of 4: 1 to 2: 1, the predominant species will be epoxidized vegetable oil monoacetate, the preferred embodiment of the present invention.

The phthalate-free plasticizer compositions of the present invention are applied to thermoplastic polymer formulations, preferably PVC. Additionally, the formulations may contain additives commonly used in the preparation of plasticized polymers, such as stabilizers, antistatic agents, flame retardants, pigments and dyes, impact modifiers, reinforcing agents, among others. The plasticizing compositions of the invention are characterized in that they are phthalate free and comprise a mixture of epoxidized vegetable oil esters, the major component of which is the epoxidized vegetable oil monoacetate.

In Figures 1 and 2 the substantial improvement of the PVC properties containing the plasticizer composition of the present invention is demonstrated, specifically the specific deformation at break (%) and the maximum stress supported by the plasticized PVC measured in Kgf / mm ² . Tables 1 and 2 below show the comparison of these properties in PVC compositions containing the inventive plasticizers (XYK) and the usual state of the art plasticizers DOP (dioctyl phthalate), DINP (diisononyl phthalate). The improvement in specific rupture strain (%) and maximum stress (kgf / mm ² ) of the PVC composition with the plasticizer of the present invention is significantly greater than that of the prior art PVC compositions with plasticizers.

TABLE 1: Specific Deformation at Break (%}

100 Plasticizer PCR 80 Plasticizer PCR

60 Plasticizer PCR 40 Plasticizer PCR

Original Original

PDO 345.3 PDO 290.9

DINP 339 DINP 293.6

XYK 358 XYK 310.7 TABLE 2: Maximum Tension (kgffrnm ² ) 100 plasticizers PCR gQ CR plasticizers

50 Plasticizers PCR 40 Plasticizers PCR

The following are exemplary embodiments of the preparation of the plasticizer compositions according to the invention. However, it should be understood that such examples are provided for illustrative purposes only and that various modifications or changes, in light of the embodiments disclosed herein, will be suggestive to those skilled in the art and should be included within the spirit and scope of this description and scope of the claims. that accompany it.

EXAMPLES

EXAMPLE 1

Glycerin triacetate epoxidized vegetable oil transesterification

54.5 g of glycerine triacetate was transesterified with 472 g of epoxidized soybean oil in the presence of 2.1 g of sodium methoxide, the mixture being heated to 80 ° C. The mixture was allowed to react for 2 hours. The epoxidized vegetable oil monoacetate obtained has the following characteristics:

EXAMPLE 2

Application to the Final Product Formulations FOR1-FOR15 contained in

Table 1 below for performance verification of the resulting products. Formulations FOR1-FOR5 comprise, as a primary plasticizer, the plasticizing compositions of the present invention; FOR6-FOR10 formulations comprise, as a primary plasticizer, dioctyl phthalate (DOP); and FOR11-FOR15 formulations comprise, as a primary plasticizer, diisononyl phthalate. The amounts of the ingredients in Table 1 are in PCR (PIECES PER 100 PVC RESIN). The Shore A hardness test was performed as known to those skilled in the art: in a becker, the materials that make up the formula were weighed and mixed. The mixture was then calendered at 160 ° C, pressed 6 mm thick at 165 ° C, and heated at 23 ° C for 24 hours. Then measurements were taken on the BAREISS durometer according to AST D-2240. Table 1: Formulations for obtaining plasticized PVC and resulting hardness

As can be seen from the Shore A hardness results, the performance of the phthalate-free plasticizer compositions of the invention was equivalent, and even (in most tests) superior to that of the primary plasticizers. such as the breaking load and elongation which showed higher values. For example, when using PVC with plasticizer in shoe crystals, where the breaking load was 11.56% higher and the elongation was 7.1% higher on a 65 SHORE A hardness crystal when compared to PVC containing state plasticizers. of technique; In use in wire and cable compounds, the performance of PVC with the plasticizer of the invention had a 2.5% higher breaking load and a 1.85% greater elongation when compared to PVC containing prior art plasticizers.

Articles molded with plasticized PVC with the fatalate-free plasticizer composition of the present invention showed good performance and compliance with the Brazilian technical standards for each of these articles, as shown in Table 2 below.

Table 2: Articles made of PVC plastic containing plasticizers compositions of the invention

Article Technical Standard / Test

Insulation Cables, Class Meets NBR NM-247/3 Thermal 70 ° C

PP cable Meets the standard NBR 13249 / N - 247-5

Free PVC stretch film Total phthalate migration test did not occur

Crystal Product for Meets Requirements

hoses

Sole Product from Meets Requirements

footwear

Product for articles that have a 50 ° C exudation test requiring absence for 1 week - no exudation has occurred All publications and patent applications mentioned herein are indicative of the level of those skilled in the art to which the invention relates. All publications and patent applications are incorporated herein by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference.

Although certain embodiments have been described, they have been presented as an exemplary mode only, and there is no intention to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; Moreover, various omissions, substitutions and changes in the form of embodiments described herein can be made without departing from the spirit of the inventions. The claims accompanying this description and its equivalents are considered to cover such forms or modifications to the extent that they may be within the scope and spirit of the inventions.

Claims

1. Phthalate-free primary plasticizer composition, characterized in that it comprises derivatives of vegetable oils, said derivatives being esterification products of epoxidized vegetable oils, mainly monoacetates of epoxidized vegetable oils.

Composition according to Claim 1, characterized in that it has an oxiranic index in the range of 5.0 to 5.8%, and an acidity index in the range of 0.3 to 0.6 mg / g of sample.

Composition according to Claim 1, characterized in that said vegetable oil is soybean oil.

Composition according to Claim 1, characterized in that it is used for the plasticization of polyvinyl chloride.

5. Process for obtaining a plasticizer containing epoxidized vegetable oil monoacetate as a major component, said process comprising the transesterification reaction between an epoxidized vegetable oil, or a mixture of epoxidized vegetable oils with glycerine triacetate present in the mass. reaction at a molar ratio in the range of about 2: 1 to 4: 1.

Process according to Claim 5, characterized in that said reaction is carried out in the presence of a transesterification catalyst.

Process according to claim 6, characterized in that said catalyst is used in a proportion in the range 0.05 to 1.0% (w / w) based on the total amount of epoxidized vegetable oil esters and glycerine triacetate used.

Process according to Claim 5, characterized in that said transesterification reaction is carried out at a temperature in the range of 50 to 180 ° C.

Process according to Claim 5, characterized in that said transesterification reaction is carried out for a period of time ranging from 1 hour to 5 hours.

Process according to Claim 5, characterized in that said molar ratio is in the range from about 4: 1 to 2: 1.

Process according to Claim 6, characterized in that the transesterification catalyst is selected from the group consisting of basic compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium methoxide, sodium ethylate; or tin (IV) compounds such as dibutyl tin butyrate.

Process according to claim 5, characterized in that the epoxidized vegetable oil is selected from the group consisting of soybean oil epoxide, flaxseed oil epoxide, sunflower oil epoxide, rapeseed oil epoxide, epoxide of castor oil, canola oil epoxide, palm oil epoxide, peanut oil epoxide or mixtures thereof.

Use of the composition of claim 1 characterized in that it is in the plasticization of polyvinyl chloride to improve its processability.

.14. Use of the composition of claim 1 characterized in that it is in the preparation of yarn, cables or shoes.