RU2487147C1 - Method of producing polyvinyl chloride based polymer nanocomposition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method of producing a polyvinyl chloride based polymer nanocomposition involves mixing powdered polyvinyl chloride, an impact strength modifier, a complex stabiliser and a nano-additive selected from carbon nanotubes, copper oxide and aluminium oxide, in amount of 0.002-0.08 pts.wt. The polyvinyl chloride is pre-mixed with the nanoadditive in ratio of 100:0.1-5 pts.wt and the obtained concentrate is added to the main composition in amount of 2-5 pts.wt.

EFFECT: improved processing and operational characteristics of the composition, uniform distribution of the small quantity of the nano-additive.

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Description

The invention relates to the production of structural, including building, materials, and in particular to a technology for the production of polyvinyl chloride compositions with nano-additives.

Known methods for producing polymer compositions with nanoadditives based on a thermoplastic binder (polypropylene, low and high density polyethylene, polyvinyl chloride (PVC) and polystyrene), which include the introduction of nanoadditives in monomers with further mixing in the main polymer [Preparation and mechanical properties of solid-phase grafting nanocomposites of PVC / graft copolymers / MMT / Z. Dunbai, C. Changgen, J. Demin // Journal of Wuhan University of Technology. 2006, No. 4, Vol.21, P.26-30]. Nanoparticle and PVC are mixed until homogeneous, after which monomers of butyl acrylate, methyl methacrylate, maleic anhydride, benzoperoxide are pre-mixed with each other and mixed. The mixed composition is sealed, heated at 80 ° C for 4-6 hours

The main disadvantages of this method include the complexity and the need for significant re-equipment, re-equipment of existing production for this type of production due to emerging new technological operations and the lack of “flexible” production.

A known method of preparing polymer compositions with nanoadditives, which consists in the introduction of nanoadditives directly in the preparation of the composition or by mixing in the melt. The authors consider the combination of [Material properties of nanoclay PVC composites / W.Awad, G. Beyer, D. Benderly // Polymer. 2009. Vol.50, P.1857-1867] nanoadditives with diisodecyl phthalate in the mixer for 5 minutes at 4000 rpm with the addition of a polar activator and subsequent mixing with PVC.

The disadvantages of the compositions obtained in this way include the relatively high content of the introduced nano-additives and low values of the physicomechanical characteristics obtained.

A known method, comprising mixing powdered PVC with a nanoadditive and other components in a closed mixer [PVC-MWNT (Multiwall carbon nanotube) nanocomposites / K. Leskovics, I. Velki, K. Marossy. // Material Sciences and Engineering. 2009. Vol. 34/2, P.61-67]. The method of preparation is as follows: the suspended components are mixed at room temperature in a closed mixer.

The main disadvantages of this method include the difficulty of uniformly distributing a small amount of nanoscale additives (the minimum percentage of nanoparticles is 5%), as a result, an increase in water absorption and a decrease in strength, fluidity and thermal stability.

The analysis of the technique and the identification of sources containing information about analogues of the claimed invention made it possible to establish that no analogues were found that are characterized by features identical to all the essential features of the claimed invention. Therefore, the claimed invention meets the condition of "novelty."

The objective is to obtain PVC nanocomposites with improved technological and operational characteristics, such as strength index, melt flow and thermal stability, ensuring uniform distribution of a small amount of nano-additives.

The result is achieved in that in the method for producing a polymer nanocomposite based on PVC, which consists in mixing powdered PVC, impact modifier, complex stabilizer, nanoparticles, according to the invention, PVC is pre-mixed with a nanoparticle selected from carbon nanotubes, copper oxide and alumina, in the ratio 100: 0.1-5 parts by weight, then the resulting concentrate is introduced into the main composition in an amount of 2-5 parts by weight, while the amount of nano-additives in the composition is 0.002-0.08 parts by weight.

The result is also achieved by the fact that for the preparation of the premix mix 100 m.h. powdered PVC with 0.05-5 m.h. nanoadditives.

To obtain a polymer nanocomposite based on PVC, components were used that satisfy the following requirements:

Suspension polyvinyl chloride grade C7058M (GOST 14332-78)

Integrated stabilizer, for example Interstab (certificate No. 99-00244)

Impact modifier, e.g. FM-22

As a nanoadditive, one can use: various allotropic forms of carbon (carbon single and multilayer nanotubes, fullerenes), layered silicates, aerosil, titanium dioxide, nanosized metal powders, polymer additives.

A polymer nanocomposite based on PVC was prepared as follows. Premix was prepared according to the following procedure.

Powdered PVC in an amount of 100 m.h. mixed with 0.05-5 m.h. nanoparticles were then subjected to thorough high-energy, mechanochemical treatment by mixing in a planetary ball mill or ball mill at 100-700 rpm for 3-40 minutes. This type of combination under the influence of shock and shear loads contributes to uniform dispersion of nanoscale additives.

The finished premix was mixed with pure PVC powder to obtain a given concentration of nanoparticles in the composition. After that, the remaining components were added: the Interstab complex stabilizer in an amount of 3-7 m.h. and impact modifier FM-22 in the amount of 5-8 m.h.

To study the properties of polymeric nanocomposites based on PVC, samples in the form of films were made. Film samples were prepared by thermoplastication on laboratory rollers with a 1: 1.25 friction at a roll temperature of 90-100 ° C for 5-6 minutes. Rolling was carried out with a thickness of the gap between the rolls of 8-13 microns.

Example 1. According to the invention, a premix consisting of 100 parts by weight was prepared. PVC and 0.1 m.h. multilayer carbon nanotubes (CNTs) from Arkema (France).

A composition with a given content, for example, 0.002 m.h. CNTs were prepared in the following ratio of components, m.h .:

PVC 98 Impact modifier FM-22 5 Integrated Stabilizer Interstab four Premix 2.002

Example 2. According to the invention, a premix consisting of 100 parts by weight was prepared. PVC and 5 m.h. nanosized alumina powder (produced by Tomsk Polytechnic University).

A composition containing, for example, 0.08 m.h. aluminum oxide, was prepared in the following ratio of components, parts by weight:

PVC 98.4 Impact modifier FM-22 5 Integrated Stabilizer Interstab four Premix 1.68

Example 3. According to the invention, a premix consisting of 100 parts by weight was prepared. PVC and 1 m.h. nanosized powder of copper oxide (manufactured by Tomsk Polytechnic University).

A composition containing, for example, 0.05 m.h. copper oxide, was prepared in the following ratio of components, parts by weight:

PVC 95 Impact modifier FM-22 5 Integrated Stabilizer Interstab four Premix 5.05

The properties of the compositions are presented in the table.

Comparative characteristics of PVC compositions, the initial and modified nanoparticles according to examples 1-3 Nano-additive (per 100 parts by weight of PVC) Indicator Tensile strength, MPa Melt Flow Index (MFI), g / 10 min Thermostability, min Without nano-additives (control) 36 0.15 41 Modified multilayer CNTs: 0.002 m.h. (0.0018%) 46 0.26 66 Modified by nanosized alumina powder: 0.008 mph (0.0073%) 40 0.19 61 Modified by nanosized copper oxide powder: 0.005 m.h. (0.0046%) 41 0.23 63 Prototype - dry mix with: 3% Nanosyl 7000 32 0.16 55

From the example of the use of CNTs as modifiers, nanosized powders of copper oxide and alumina, it is seen that the introduction of nanoadditives in accordance with the invention improves thermal stability, melt flow rate (MFR) and strength indices due to a more uniform distribution of the ultra-small amount of nanoadditives, resulting in a lower final cost products manufactured by this technique.

Claims (1)

A method for producing a polymer nanocomposite based on polyvinyl chloride, which consists in mixing powdered polyvinyl chloride, impact modifier, complex stabilizer, nanoparticles, characterized in that polyvinyl chloride is pre-mixed with a nanoparticle selected from carbon nanotubes, copper oxide and aluminum oxide, at a ratio of 100: 0 1-5 parts by weight, then the resulting concentrate is introduced into the main composition in an amount of 2-5 parts by weight, while the amount of nano-additives in the composition is 0.002-0.08 parts by weight.