RU2508197C1 - Method for production of profile from pvc for window and door units containing silver ions with antibacterial properties - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: according to the method for production of profile from PVC for window and door units, dry components of composition are mixed in blending unit. Obtained dry mixture is supplied to vibroscreen, and then dry mixture is exposed during at least one day and is supplied to extrusion machine. Dry mixture is extruded and is simultaneously supplemented by silver-containing substance.

EFFECT: obtaining polymer profile for window and door units with persistent antibacterial properties.

7 cl, 1 tbl, 3 ex

Description

The invention relates to the field of construction and is intended for the manufacture of PVC profiles for window and door blocks containing silver ions with antibacterial properties.

Microbiological corrosion of building and finishing materials causes significant damage to finished structures, so the question of preventing damage caused by microorganisms, molds and other organisms harmful to humans is extremely important. The complexity of the problem is compounded by the fact that microorganisms have the ability to adapt to new living conditions, in particular to the chemicals used to destroy them.

The growth of microorganisms on polymeric material can lead to the formation of mucus, spots, microcracks, mycelium, and the appearance of a smell. Found in many cases, and deeper damage. The stability of PVC window structures depends on the micro-resistance of the individual components of the composition.

In addition to the components of the formulation, which should be as susceptible to microbes and mold as possible, we add a silver-containing substance to impart antimicrobial properties to the profile for window and door blocks and have a beneficial effect on humans.

Silver has low physiological activity; it is harmless to humans and domestic animals.

Human action

Tests at the Federal State Budget Institution Scientific Research Institute of Disinfectology of Rospotrebnadzor in Moscow dated December 20, 2011 established that the profile for window and door blocks containing silver ions has an antimicrobial effect, including against bacteria S.aures (staphylococcus) and E. coli (E. coli ), providing after 24 hours the reduction of contamination of the profile surfaces to 79.3%.

Process chemistry

Metals depending on the position in the table D.I. Mendeleev can enter into a variety of reactions with PVC. The principle of binding in the macromolecule of PVC free Cl with the help of lead Pb is the basis for the stabilization of polyvinyl chloride from thermal degradation.

As for silver ions, Ag, being added to PVC in small quantities, they do not affect the stabilization of PVC, that is, they do not participate in a qualitative reaction. Being added in large quantities (1: 1), Ag silver does not affect the rate of dehydrochlorination of PVC in the absence of HCl, but, like mercury, it reduces the rate of autocatalytic decomposition of PVC, i.e. while leaving PCl in the reaction zone.

The prior art method for manufacturing a profile material suitable, in particular, for the manufacture of windows and doors using thermoplastic material, by thermoplasticizing the material and continuous profile molding of thermoplastic material, comprising the following operations: the formation of the first component of the mixture from thermoplastic plastic waste; preparing the second component of the mixture containing additives; intensive mixing of the first and second components of the mixture with each other, compaction, and by thermoplasticization of the first component of the mixture, preparing a mixture suitable for continuous profile molding. A mixture suitable for continuous profile molding is injected under pressure into the profile-forming channel until it is filled, a thick-walled profile preform is formed in it, at least partially cured by cooling, and then it is removed from the profile-forming channel in the form of a length corresponding to the length of the profile-forming channel ; the profile billet is subjected to a shrinkage process in individual sections during the holding time, and the holding time is sufficient for a substantial part of the total expected shrinkage to occur; after the exposure time, the profile workpiece is subjected to shaping by cutting by cutting with removal of material, at least on certain parts of its perimeter with the formation of an intermediate profile; on the intermediate profile, at least part of its perimeter is coated in the form of a layer that improves the surface (RU 2177412, 12.27.2001).

A known process for the production of profiled materials, in particular for the production of doors and windows, in which a component of a thermoplastic material and a second component containing additives, are mixed and compacted to form a mixture. Thus, the thermoplastic component is thermally plasticized. The forming mixture is formed into a profile material, which can then be further processed into a mold and coating to form the final product (US 6237208, May 29, 2001).

A known method of manufacturing from polyvinyl chloride (PVC) foamed wood-plastic windows from sectional material, in which the sectional material is obtained from the following components of the raw material, in parts by weight: 60-85 parts of PVC, 10-25 parts of wood fiber, 0.2-0.8 parts of a foaming agent azodicarbonamide, 4-8 parts of a foaming regulator, 5-8 parts of a stabilizer, 1-6 parts of a high impact modifier, 8-15 parts of calcium carbonate and 2-6 parts of epoxidized soybean oil. The preparation of the method includes the following steps: the raw materials are placed in a high-speed mixer and mixed, after mixing the raw materials evenly, the mixture is delivered to a cold mixing machine, cooled to room temperature and unloaded for later use, and then extruded in a granulation extruder (CN 102108168, 06/29/2011 )

The disadvantage of the obtained profiles is that they do not have antibacterial properties. In addition, the disadvantage of the first method is its low productivity, and the second method (manufacturing PVC foamed wood-plastic windows from sectional material) - significant manufacturing complexity, the inability to obtain this profile on conventional mixing and extrusion equipment - it is necessary to have more sophisticated additional equipment for processing wood filled mixtures and foam profiles

The technical result achieved by the implementation of this invention is to obtain a polymer profile for window and door blocks with stable antibacterial properties by adding silver-containing substance (silver ions) directly to the extruder, which allows you to evenly distribute silver ions in the mass of the profile, due to which bactericidal properties of the entire profile, which are maintained throughout the operation of the profile, since silver ions are located not only on the surface of the profile, about and within it (i.e. not used up as if silver ions are deposited as a coating on the airfoil surface).

The specified technical result is achieved in a method of manufacturing a PVC profile for window and door blocks, in which the dry components of the composition are mixed at the mixing unit, then the resulting dry mixture is sent to a vibrating screen for sifting, after which the dry mixture is kept for at least 1 day and served on the extruder, while the extrusion of the dry mixture is carried out with the simultaneous addition of silver-containing substances.

On the extruder, under the influence of mechanical loads and temperature, the dry mixture is mixed with the silver-containing substance using the screws of the extruder and it passes into the molten mass, which exits through the die to shape the profile, then the mass is fed to calibrators, where the mass is cooled by vacuum and cold water and give geometric shapes to the finished profile.

The mixing plant consists of a hot mixing mixer, which provides heating of the composition to a temperature of 90-140 ° C, and a cold mixing mixer, which provides cooling to 20-90 ° С.

Additionally, after the calibrators, the profile in the form of a continuous tape is sent through the cooling baths, where, under the influence of cold water with a temperature of 10-14 ° C, the final cooling takes place, then the cooled profile passes to the gluing station of a self-adhesive protective film and a cutting device, on which the profile is cut into whips, after that, chopped profile whips are laid on a pallet.

The mass is directed through the cooling baths at a constant speed, which is carried out and regulated by a caterpillar exhaust device.

As a silver-containing substance, either silver nitrate AgNO ₃ , or silver proteinate, or silver arceinate Ag ₃ AsO ₄ , or silver trithioortho arsenite (1) Ag ₃ AsS ₃ , or silver bromide AgBr, or silver bromate (I) AgBrO ₃ , or chloride is used silver (I) AgCl, or silver oxide (III) -silver (I) Ag ⁺ Ag ³⁺ O ₂ (Ag ₂ O ₂ ) and other silver-containing substances.

A method of manufacturing a PVC profile for window and door blocks is as follows.

Factors affecting the mixing of the PVC composition.

PVC composition for the production of profiles for window and door blocks with silver ions with antimicrobial properties is a multicomponent system for which mixing is a mandatory operation. In this case, the main attention should be paid to the homogeneity of the mixture, since the uniform distribution of all components of the formulation and the silver-containing substance, in particular, is the main condition for antimicrobial treatment of the entire mass of the profile. The mixing process is affected by the aggregate state of the products being mixed, the difference in their densities, particle size distribution and morphology, the order of introduction of the components, the mixing mode, the order of introduction of solid components is reflected both in the rate of heating of PVC and, consequently, the duration of the mixing cycle, and in the dispersion of components and their effectiveness. Lubricants are best administered after mixing PVC with other additives at a temperature of about 20 ° C below the desired final temperature and at a higher stirrer frequency. It is recommended to add lubricant to the composition of the window profile at 100 ° C, then bring the temperature to 120 ° C and quickly cool the composition by transferring it to a cold mixer. In order to avoid excessive heat load, the resulting hot PVC composition from a high-speed hot mixer should be converted to cold and cooled with slow stirring to 35-40 ° C.

PVC choice

To prepare a PVC composition with silver ions, it is necessary to take into account the role of each of the components that make up the composition, the possibility of their interaction with each other, with the products of PVC degradation, with oxygen and other chemical agents. The processing efficiency of compositions of the same composition according to the same technological scheme differs significantly depending on the properties of the original powdered PVC.

The main indicators that determine the behavior of PVC during processing into a silver-containing window profile, as well as its properties, include the molecular weight of the polymer, the morphological characteristic of the grain, average particle size, pycnometric density, and thermal stability. The main indicator, which can optionally be changed within wide limits due to a change in the polymerization temperature or due to the introduction of various additives (chain growth regulators or comonomers), is the molecular weight.

Most often, PVC with a Fikentcher constant of 50-75 is used to process hard products on an extruder. In our case, you can use suspension PVC with a constant of F 60-72.

For industrial PVC grades used for profile extrusion for window and door blocks containing silver ions, bulk density is very important, which determines the performance of the extrusion lines and the cost-effectiveness of transporting PVC.

Profile Extrusion Process Requirements

One of the most important stages in extrusion is plasticization as a means of improving the distribution of silver ions in the mass of the PVC profile for window and door blocks containing silver ions. In this case, the morphology of PVC grains plays an important role, which determines the quality of the extrudate, the thermophysical and rheological properties of the composition. In various cases, an individual approach to the selection of extrusion machines and processing conditions is required. In all cases, equipment for processing PVC should be made of corrosion-resistant metals, forming heads (dies) should not have dead zones in which stagnation of the melt and polymer decomposition would occur.

Since the polymer is subjected to high pressure and high temperatures at the same time, and the mass velocity along the channels of the worm is low, it is necessary to pay special attention to the choice of effective stabilizing systems, because high viscosity prevents the achievement of complete homogenization, in our case, the content of silver ions in the mass of the profile is violated.

Complex stabilizers based on lead, such as IKA 6727, NaftosafeGWX 630 Y, Naftomix GWX 527D, Naftomix GWX 200A, contain 20-40% lead, are added to the formulation in an amount of 2-4%, affect not only the thermal stability of PVC. With their help, you can change the melting rate and some other physical properties of the composition: melt viscosity, extrudate density, equipment performance.

To obtain a bactericidal profile for window and door blocks with silver ions, it is necessary to achieve homogenization - a uniform distribution of silver ions in the polymer profile. Good distribution can be achieved by adding a silver-containing material in the extrusion step. The distribution of silver ions is necessary so that the entire surface of the profile has bactericidal properties.

The dry components of the composition for the production of the window profile - PVC, filler, stabilizer, additives, are hung according to the recipe and fed to the mixing unit (mixing line) - to the mixing stage.

The mixing installation includes a hot mixing mixer, providing heating of the composition to a temperature of 90-140 ° C, and a cold mixing mixer, providing cooling to 20-90 ° C.

Dry components of the composition / raw materials (PVC, filler, stabilizer, additives) are fed to the hot mixing mixer. In the hot mixing mixer due to friction and (or) additional heat supply, the components of the composition are heated and the composition is uniformly distributed. Mixing is carried out to a temperature of 90-140 ° C (the heating temperature depends on the properties that need to be given to the finished composition), then the composition is poured into a cold mixing mixer, where during slow rotation there is cooling to a temperature of 20-90 ° C (the cooling temperature depends on the method its further processing).

The composition for the antimicrobial window profile is shown in the table.

The hot mixing mixer may consist of a fixed cylindrical chamber and blades inside, during rotation of which, due to the friction force between the components of the PVC composition, heating occurs. And cooling in a cold mixing mixer can occur due to the circulation of water in the inner jacket of this mixer.

The resulting dry mixture is sent to a vibrating screen for sifting from dirt and lumps of the mixture. After sifting, the dry mixture is aged for at least 1 day before being fed to the extruder (extrusion line).

In the finished composition, directly when fed to the extruder, it is fed using a mechanical device, for example, a soda feeder, screw feeder, pump, providing a uniform supply, silver-containing substance. With this process, the bulk of the mixing takes place directly in the areas of operation of the screws of the extruder. In this embodiment, when silver-containing material is added directly to the extruder, the necessary distribution of silver ions in the mass of the PVC profile occurs.

The molten mass leaves the extruder through a die, which gives shape to the PVC profile.

As a silver-containing substance, silver nitrate AgNO ₃ (98-99% silver), silver arceinate Ag ₃ AsO ₄ (85-99% silver), silver bromide AgBr (85-99% silver) and other silver-containing substances are used.

From the die, the hot composition passes to calibrators, where, under the influence of vacuum and cold water, the PVC profile is pre-cooled and acquires the final geometric dimensions. After the calibrators, the PVC profile in the form of a continuous tape passes through the cooling baths, where, under the influence of cold water with a temperature of 10-14 ° C, the profile is finally cooled. A constant profile exit speed is carried out and regulated by a crawler exhaust device.

Then the profile passes to the gluing station of a self-adhesive protective film and a cutting device, on which the profile is cut into whips of a certain length.

After that, the chopped profile whips are stacked on a pallet, packed in plastic film, labeled and sent to the warehouse.

Example 1

Dry components of the composition:

PVC - 100 mph

CaCO ₃ -6 pbw

Integrated lead-based stabilizer - 2 mph

Impact modifier - 3 m.h.

Titanium Dioxide - 2-4 mph

served in a hot mixer. In the hot mixing mixer due to friction and (or) additional heat supply, the components are heated and the composition is uniformly distributed. Mixing is carried out to a temperature of 90 + -10 ° С (this temperature allows to obtain the following properties of the finished composition: sufficient distribution of PVC, filler, additives, swelling of PVC, the transition of additives to (on) the surface of the polyvinyl chloride particles), then the composition is poured into a cold mixing mixer, where during slow rotation there is cooling to a temperature of 30 + -10 ° C (this cooling temperature allows you to use the processing method: the minimum aging time of the composition). Then it is sent to a vibrating screen for sifting from dirt and lumps of the mixture. After sifting, the dry mixture is aged for at least 1 day and fed to the extruder. In the finished composition, directly when fed to the extruder, a screw feeder is fed by means of a mechanical device, ensuring a uniform supply of silver nitrate AgNO ₃ in an amount of 0.002 parts by weight containing silver ions. With this process, the bulk of the mixing takes place directly in the areas of operation of the screws of the extruder. In this embodiment, when silver-containing material is added directly to the extruder, the necessary distribution of silver ions in the mass of the PVC profile occurs.

Example 2

Dry components of the composition:

PVC - 100 mph

CaCO ₃ - 10 m.h.

Integrated lead-based stabilizer - 3 m.h.

Impact modifier - 5 m.h.

Titanium Dioxide - 3 m.h.

served in a hot mixer. In a hot mixing mixer, the components are heated and the composition is uniformly distributed. Mixing is carried out to a temperature of 115 + -10 ° С (this temperature allows you to obtain the following properties of the finished composition: good distribution of PVC, filler, additives, swelling of PVC, the transition of additives to (on) the surface of the polyvinyl chloride particles), then the composition is poured into a cold mixing mixer, where during slow rotation there is cooling to a temperature of 60 + -10 ° C (this cooling temperature allows you to use the processing method: reduction of energy costs for heating in an extruder). Then it is sent to a vibrating screen for sifting from dirt and lumps of the mixture. After sifting, the dry mixture is aged for at least 1 day and fed to the extruder. In the finished composition, directly when fed to the extruder, a soda feeder is fed using a mechanical device, which ensures a uniform supply of silver arseinate Ag ₃ AsO ₄ (85-99% silver) in an amount of 0.005 parts by weight containing silver ions. With this process, the bulk of the mixing takes place directly in the areas of operation of the screws of the extruder. In this embodiment, when silver-containing material is added directly to the extruder, the necessary distribution of silver ions in the mass of the PVC profile occurs.

Example 3

Dry components of the composition:

PVC - 100 mph

CaCO ₃ - 15 m.h.

Complex stabilizer based on lead - 4 m.h.

Impact modifier - 6 mph

Titanium Dioxide - 4 m.h.

served in a hot mixer. In a hot mixing mixer, the components are heated and the composition is uniformly distributed. Mixing is carried out to a temperature of 130 + -10 ° С (this temperature allows to obtain the following properties of the finished composition: good distribution of PVC, filler, additives, swelling of PVC, the transition of additives to the (on) the surface of the polyvinyl chloride particles), then the composition is poured into a cold mixing mixer, where during slow rotation there is cooling to a temperature of 90 + -10 ° C (this cooling temperature allows you to use the processing method: reducing energy costs for heating in an extruder). Then it is sent to a vibrating screen for sifting from dirt and lumps of the mixture. After sifting, the dry mixture is aged for at least 1 day and fed to the extruder. In the finished composition, directly when fed to the extruder, a pump is supplied using a mechanical device to ensure uniform supply of AgBr silver bromide (85-99% silver) in an amount of 0.01 mb containing silver ions. With this process, the bulk of the mixing takes place directly in the areas of operation of the screws of the extruder. In this embodiment, when silver-containing material is added directly to the extruder, the necessary distribution of silver ions in the mass of the PVC profile occurs.

Claims (7)

1. A method of manufacturing a PVC profile for window and door blocks, characterized in that the mixing unit mixes the dry components of the composition, then the resulting dry mixture is sent to a vibrating screen for sifting, after which the dry mixture is kept for at least 1 day and served an extruder, while the extrusion of the dry mixture is carried out with the addition of silver-containing substances. 2. The method according to claim 1, characterized in that on the extruder under the influence of mechanical loads and temperature, the dry mixture is mixed with a silver-containing substance using the screws of the extruder and its transition into the molten mass, which goes through the die to shape the profile, then the mass is fed to calibrators, where, under the influence of vacuum and cold water, the mass is cooled and geometric shapes of the finished profile are attached. 3. The method according to claim 1, characterized in that the mixing unit consists of a hot mixing mixer, providing heating of the composition to a temperature of 90-140 ° C, and a cold mixing mixer, providing cooling to 20-90 ° C. 4. The method according to claim 2, characterized in that, in addition, after the calibrators, the profile in the form of a continuous tape is sent through cooling baths, where, under the influence of cold water with a temperature of 10-14 ° C, the final cooling takes place, then the cooled profile passes to the gluing station with a self-adhesive protective films and a cutting device on which the profile is cut into whips, after which the cut profile whips are laid on a pallet. 5. The method according to claim 4, characterized in that the mass is directed through the cooling baths at a constant speed, which is carried out and regulated by a caterpillar exhaust device. 6. The method according to claim 1, characterized in that the composition contains the following ratio of dry components, wt.%:
PVC - 100 mph
CaCO ₃ - 6-15 mph
Integrated lead-based stabilizer - 2-4 mph
Impact modifier - 3-6 mph
Titanium Dioxide - 2-4 mph
Silver nitrate - 0.002-0.01 m.h. 7. The method according to claims 1 or 6, characterized in that as the silver-containing substance, either silver nitrate AgNO ₃ or silver proteinate or silver arceinate Ag ₃ AsO ₄ or tritioortho arsenite silver (I) Ag ₃ AsS ₃ , or silver bromide AgBr, or silver bromate (I) AgBrO ₃ , or silver chloride (I) AgCl, or silver oxide (III) -silver (I) Ag ⁺ Ag ³⁺ O ₂ (Ag ₂ O ₂ ).