WO2013093237A1

WO2013093237A1 - Stabilized composition based on a chlorinated thermoplastic material

Info

Publication number: WO2013093237A1
Application number: PCT/FR2012/000529
Authority: WO
Inventors: Christian Maliverney; Laurent Saint-Jalmes
Original assignee: Bluestar Silicones France
Priority date: 2011-12-23
Filing date: 2012-12-18
Publication date: 2013-06-27
Also published as: FR2984905A1

Abstract

The invention relates to a stabilized composition based on a chlorinated thermoplastic material and an additive that is an organic compound.

Description

STABILIZED COMPOSITION BASED ON THERMOPLASTIC MATERIAL

CHLORINATED

The present invention relates to a stabilized composition based on a chlorinated thermoplastic material and an organic compound.

Halogenated polymers and more particularly polyvinyl chloride (PVC) are widely used polymers in many different and varied fields. Pure PVC is a rigid, mechanically strong material that is relatively resistant to weather, water and chemicals. It is electrically insulating but quite unstable to heat and light. Thus, under the influence of heat, PVC undergoes a deep degradation, accompanied by a characteristic coloration. Degradation mechanisms have been widely studied and it is recognized that the induction of thermal degradation of PVC is caused by the presence of "labile chlorine atoms" causing a dehydrochlorination reaction giving rise to conjugated double bond sequences, responsible for parasitic staining, this reaction being itself catalyzed by free hydrochloric acid. The PVC then takes a brown color which turns with time to black. In addition to these coloring phenomena, parasitic crosslinking also affects the physical properties of the material.

It is for this reason that many thermal stabilizers have been developed for PVC. However, it is still impossible to act on the induction of thermal degradation of PVC which is inherent in the very structure of this polymer. Thus, the function of the thermal stabilizers of PVC is to slow the spread of the dehydrochlorination chain and eliminate the hydrochloric acid released by this reaction.

Among the stabilizers used, lead stabilizers are the oldest but due to very strong environmental pressure, there is a gradual ban in the world. Organotins (organotins) are also widely used. Various types of organotins, particularly mixtures of mono- and diorganotin compounds, are used as stabilizers, essentially for producing rigid packaging films, bottles, roof coatings and clear rigid building boards. Among the most useful are tin carboxylates which are of two types:

the soaps such as dibutyltin dilaurate, and

- the maleates. However, these alkyltin derivatives, although very effective, have the disadvantage of being toxic (CMR2 toxic for reproduction). Thus, for sustainable development, it therefore appears necessary to develop stabilizers for non-toxic chlorinated thermoplastics.

The essential objective of the present invention is therefore to find novel substitution stabilizers for lead or tin derivatives.

Another essential objective of the present invention is to propose new articles prepared from a composition containing a chlorinated thermoplastic material additive with the new stabilizers according to the invention.

These and other objects are achieved by the present invention which firstly relates to a composition comprising:

a) at least one chlorinated thermoplastic material M, and

b) at least one thermal stabilizer A which is a non-silylated organic compound of the guanidin family which is stituated and corresponds to the general formula (I):

(I)

in which,

- The radicals R ¹ , R ² , R ³ , R ⁴ or R ^{5, which are} identical or different, represent, independently of each other, a linear or branched monovalent alkyl group, a cycloalkyl group or a (cycloalkyl) alkyl group. , the ring being substituted or not and may comprise at least one heteroatom or a fluoroalkyl group, an aromatic group an arylalkyl group, a fluoroalkyl group, an alkylamine or alkylguanidine group,

the radicals R ¹ , R ² , R ³ or R ⁴ may be linked in pairs so as to form a 3-, 4-, 5-, 6- or 7-membered aliphatic ring optionally substituted with one or more substituents ,. and

with the additional proviso that the radicals R ¹ , R ² , R ³ , R ⁴ and R ⁵ do not comprise a silicon atom. The compositions according to the invention have a better thermal stability than chlorinated thermoplastic resins not additive with the stabilizer according to the invention. Thus, these compositions have a viable alternative to formulations using lead or tin derivatives.

It is to the credit of the inventors to have found, quite surprisingly and unexpectedly, that it is appropriate to use specific guanidines (guanidines 1, 1, 2,3,3-pentasubstituted) to obtain excellent stabilizers thermal for chlorinated thermoplastics such as PVC. The unsulphonized compounds according to the invention and corresponding to the general formula (I) are pentasubstituted guanidines and have the advantage of being liquid, colorless and odorless.

The stabilizer A according to the invention can be used in the composition according to the invention in amounts ranging from 0.1 to 50 parts by weight, preferably from 0.1 to 20 parts and even more preferentially from 0.1 to 10 parts. parts by weight per 100 parts by weight of the chlorinated thermoplastic material M. Thus the composition according to the invention comprises:

a) per 100 weight parts of at least one chlorinated thermoplastic material M, and b) from 0.1 to 50 weight parts of at least one thermal stabilizer A according to the invention and as described herein, and preferably from 0.1 to 20 parts by weight and even more preferably from 0.1 to 10 parts by weight.

According to a preferred embodiment the thermal stabilizer A is an unsilylated organic compound corresponding to the general formula (I) and in which:

the radicals R 1, which are identical or different, and the radical R 3 are chosen,

independently from each other, in the group consisting of: an isopropyl radical, a cyclohexyl radical and a linear or branched monovalent C 1 -C 12 alkyl radical.

the radical R2 represents a linear or branched monovalent alkyl group, a cycloalkyl group, a substituted or unsubstituted ring-substituted alkyl group and may comprise at least one heteroatom, an arylalkyl group, a fluoroalkyl group, an alkylamine or alkylguanidine group, and

the radicals R ¹ , R ² , R ³ or R ⁴ may be linked in pairs so as to form a 3-, 4-, 5-, 6- or 7-membered aliphatic ring optionally substituted with one or more substituents. For carrying out the invention, a non-silylated organic compound chosen from the group consisting of

(A4)

The chlorinated thermoplastic material M may especially consist of a chlorinated resin selected from the group consisting of homopolymers of vinyl chloride which may be optionally superchlorinated and optionally grafted copolymers, which result from the copolymerization of vinyl chloride with one or more ethylenically comonomers. unsaturated. Examples of comonomers that may be mentioned include vinylidene halides such as vinylidene chloride or fluoride, vinyl carboxylates such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylic and methacrylic acids. as well as nitriles, amides and alkyl esters which derive therefrom, in particular acrylonitrile, acrylamide, methacrylamide, methyl methacrylate, methyl acrylate, butyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, vinylaromatic derivatives such as, for example, styrenes,

vinyl naphthalenes, olefins such as bicyclo (2.2.1) hep-2-ene, bicyclo (2.2.1) hepta-2,5-diene, ethylene, propene and butene-1.

According to a preferred embodiment, the chlorinated thermoplastic material M is chosen from the group consisting of: a homopolymer of vinyl chloride, a copolymer of vinyl chloride with unsaturated comonomers and their mixtures

According to a preferred embodiment, the chlorinated thermoplastic material M is chosen from the group consisting of: a polyvinyl chloride resin, a plastisol obtained by mixing a polyvinyl chloride resin in a liquid plasticizer and their mixtures.

The compositions according to the invention may furthermore contain, depending on, in particular, the conditions for processing, and / or the applications for which they are intended, one or more additives chosen from the group consisting of: a lubricating agent, an agent plasticizer, a filler, a coloring aid, an anti-shock agent, an antistatic additive, a fungicidal additive, a blowing additive, a sun-protective additive, a processing-aids additive to improve the gelation of the ready mixture use and mixtures thereof.

The thermal stabilizer A according to the present invention may be incorporated, at the same time and / or before the additives mentioned above when it is used.

According to a particularly preferred implementation, this operation is carried out in a slow or fast mixer and the resin is introduced successively.

thermoplastic, the stabilizer according to the invention and additives and / or fillers, so as to obtain a mixture in the form of dry powder or in the form of paste. In a manner known per se, this operation can be carried out at room temperature or at a higher temperature due to the heat generated by this operation.

The heat-stabilizing action and the light of the stabilizer A according to the invention can for example be demonstrated for the articles transformed by standard tests and well known by those skilled in the art such as static thermal stability test at oven. The compositions according to the invention, in particular those based on PVC, can be injection molded, rotational molded, calendered and then thermoformed, extruded, coextruded, pressed in the form of articles such as hoses, window profiles, sheets, tubes. or, in the case of flexible resin formulations of the plastisol type, implemented by coating or dipping processes and transformed into articles such as interior and exterior coatings, in particular coated fabrics for the building industry, leather goods, etc. The transformed articles can be rigid or flexible, compact or expanded. The invention also relates to an article obtained by extrusion, extrusion blow molding, calendering, injection and intrusion, or thermoforming of the composition according to the invention and as described herein.

Finally, a last object of the invention consists in the use of the composition according to the invention and as described herein or the article according to the invention for the fields of building, packaging, electricity, electronics, medical, consumer goods and transportation.

Other advantages and features of the present invention will appear on reading the following examples given by way of non-limiting illustration.

EXAMPLES EXAMPLE 1 Synthesis of Thermal Stabilizers (A2) and (A3) According to the Invention

(A-2): 1-butyl-2,3-dicyclohexyl-1,3-dimethylguanidine

To a solution of 19.12 g of N-methyl-N-cyclohexylamine (0.169 mol) in 160 ml of hexane is added dropwise 18.38 g of cyclohexyl isocyanate (0.147 mol) and the cloudy mixture is heated for 2 hours under reflux, then evaporated to dryness to give 35 g of crude Ν, Ν'-dicyclohexyl-N-methylurea. To a suspension of 17 g of this (71.33 mmol) in 65 ml of dry toluene is added 12 g of POCI ₃ (78 mmol) over 1 h, then after a few hours at 20 ° C., 15.5 g of N-butyl- N-methylamine (0.178 mmol) are added over 2 hours, then after an additional 2 hours at 20 ° C., 50 ml of water are added. 49 g of 35% sodium hydroxide are then added with cooling, then the biphasic medium is extracted with diisopropyl ether. After drying and evaporation to dryness, the oil obtained, 26.5 g, is distilled at 180 ° C. under 1 mbar to give 21.25 g of the expected guanidine (yield 97%). (A-3: N-Butyl-N'-cyclohexyl-N-ethyl-Diperidine-1-carboxamidine

To a solution of 18.62 g of piperidine (0.219 mol) in 360 ml of hexane is added dropwise 23.8 g of cyclohexyl isocyanate (0.190 mol), then the turbid mixture is heated for 2 hours under reflux, then cooled and filtered to give 39.3 g of pure N-cyclohexylpiperidine-1-carboxamide (yield 98.3%). To a suspension of 15.05 g of this (71.6 mmol) in 65 ml of dry toluene is added 12 g of POCI ₃ (78 mmol) over 1 h, then after a few hours at 20 ° C., 18.1 g of N-butyl- N-ethylamine (0.179 mmol) are added over 2 h, then after an additional 2 h at 20 ° C., 50 ml of water are added. 49 g of 35% sodium hydroxide are then added with cooling, then the biphasic medium is extracted with diisopropyl ether. After drying and evaporation to dryness, the oil obtained, 20 g, is distilled at 85 ° C. under 1 mbar to give 17 g of the expected guanidine (yield 81%).

EXAMPLE 2 Preparation of a Composition Based on PVC of Simplified Type Containing the Stabilizers (AD to (A4) According to the Invention Operating Procedure: 100 parts by weight of a PVC resin are introduced into a mixer. (> 3000 rpm), a rise in temperature is observed At 60 ° C., variable amounts (= 1 to 40 parts) of a stabilizer according to the invention are then introduced, followed by the usual additives (pigment such as TiO2, agent

plasticizer). When the temperature reaches about 10 ° C, the PVC formulation is cooled by reducing stirring and cooling the reactor.

EXAMPLE 3

About 10 g of each of the compositions prepared according to the protocol described in Example 2 are poured onto a paper support before being introduced into an oven heated to a temperature of about 190 ° C. Samples are taken from the sheet

of induction at regular time intervals by noting their coloring. On the samples taken, the residual stability, expressed in min, is measured and measured using a dehydrochlorination bench (DHC) according to the ISO 182-2 standard. The good results of residual stability according to the DHC test highlight the good thermal stabilization properties of the stabilizers according to the invention.

Claims

1 - Composition comprising:

a) at least one chlorinated thermoplastic material M, and

in which,

with the additional proviso that the radicals R ¹ , R ² , R ³ , R ⁴ and R ⁵ do not comprise a silicon atom.

Composition according to Claim 1, comprising:

a) per 100 parts by weight of at least one chlorinated thermoplastic material M, and b) from 0.1 to 50 parts by weight of at least one thermal stabilizer A as described in claim 1, and preferably of 0.1 at 20 weight parts and even more preferably from 0.1 to 10 weight parts.

3 - The composition of claim 1 wherein the chlorinated thermoplastic material M is selected from the group consisting of: a homopolymer of vinyl chloride, a copolymer of vinyl chloride with unsaturated comonomers and mixtures thereof. 4 - The composition of claim 1 wherein the chlorinated thermoplastic material M is selected from the group consisting of: a polyvinyl chloride resin, a plastisol obtained by mixing a polyvinyl chloride resin in a plasticizer liquid and their mixtures.

5. Composition according to any one of the preceding claims, in which the composition further comprises at least one additive chosen from the group consisting of a lubricating agent, a plasticizer, a filler, a coloring aid and an anti-shock agent. an antistatic additive, a fungicidal additive, a blowing additive, a sun-protective additive, a processing-aids additive to improve the gelling of the ready-to-use mixture, and mixtures thereof.

6 - Composition according to claim 1 wherein the thermal stabilizer A is an unsilylated organic compound selected from the group consisting of the following compounds (A1) to (A4):

(A3) 7 - Article obtained by extrusion, extrusion blow molding, calendering, injection and intrusion, or thermoforming of the composition as described in any one of the preceding claims.

8 - Use of the composition as described according to any one of claims 1 to 6 or the article as described according to claim 7 for the fields of building, packaging, electricity, water, water and electricity. electronic, medical, consumer goods and transportation.