JPS5827817B2 - Method for improving the sorption capacity of substantially hydrophobic thermoplastic polymers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for improving the sorption capacity of substantially hydrophobic thermoplastic polymers.

According to the invention, therefore, in a method for improving the sorption capacity of a substantially hydrophobic thermoplastic polymer, the following steps are provided: The above-mentioned halogen is added to the polymer by contacting the above-mentioned polymer with a solution containing an elemental halogen selected from the group consisting of (b) a second step of removing the halogen-containing polymer from the solution; The above polymer is contacted with a reagent consisting of ammonia, ammonium hydroxide, formic acid or sodium bisulfite capable of reacting with elemental halogens contained in A method for improving the sorption capacity of a polymer is provided.

Polymers treated by this method surprisingly have a significantly increased ability to sorb a wide range of substances, including gases, liquids, solutes, and suspended solid particles, when compared to their untreated counterparts. It was discovered that

This increased sorption capacity is manifested by an increase in the sorption rate and rate of the substance, and also by an increase in the amount of the substance retained on the polymer.

The improved sorption properties of the polymers obtained by this process can be determined, for example, by the amount of absorption of the dye from aqueous or non-aqueous solutions, by the water content and by similar methods.

The novel method of the present invention and the polymers obtained thereby are useful in a variety of applications that take advantage of the sorption properties of polymers.

Furthermore, it has often been found that sheets or films of polymers treated, for example, by the present method have altered permeability to gases or solutes.

Such polymers can be usefully applied in ultrafiltration processes, for example for the purification of industrial wastewater, water desalination, medical dialysis or similar processes.

One important application of the invention is in the textile industry, especially for hydrophobic synthetic fibers, which have heretofore been associated with significant difficulties requiring high temperatures, high pressures and the use of various dye carriers and auxiliaries. It consists in dyeing.

Furthermore, it has been found that, in addition to improved sorption properties, the polymers treated according to this method often undergo other changes which are advantageous for use in the textile industry.

These changes are, among other things, increased loftiness, increased moisture content which makes the textile garment more comfortable, increased covering power and improved tactile feel.

Additional uses and applications of the invention are described below.

In the first step (a) of the method, a substantially hydrophobic thermoplastic polymer is contacted with a solution containing elemental chlorine, bromine, iodine, or a mixture thereof, thereby removing the elemental halogen. It is added to and introduced into the polymer.

The degree to which the addition of halogen has progressed can be understood by the change in color of the polymer; if initially colorless, the polymer gradually takes on the color of the added halogen, i.e. when chlorine is added. becomes yellow-green; when bromine is added, it becomes reddish-brown.

This method, which is carried out on hydrophobic polymers consisting of However, the exact mechanism is unknown.

Therefore, this method can be discussed from the perspective of the distribution or distribution of elemental halogen in a two-phase system comprising a halogen solution and a polymer.

A partition coefficient can be attributed to each particular system and is what determines the rate and extent of halogen addition to the polymer.

Aqueous solutions of chlorine and/or bromine are preferred for the first step (a) of the method.

This is because the aqueous solution provides a higher partition coefficient, thus increasing the rate and extent of halogen addition to the composite.

As explained below, one of the factors that determines increasing the sorption capacity of a treated polymer is generally the amount of halogen introduced into the polymer in the first step of the process.

It has also been found that the rate of introduction of chlorine and bromine into the polymer in the first step of the process is increased if the pH of the halogen-containing aqueous solution is lowered by adding an inorganic acid such as hydrochloric acid or hydrobromic acid. It was done.

Preferred pH values range from about 0 to 3, more preferably from 0 to 1.

A similar rate increase is seen when the halogen solution contains a significant concentration of the corresponding halogen ion.

Although the use of bromine appears to give slightly better results than chlorine in many cases, the difference between bromine and chlorine is not appreciable and therefore chlorine is often used in this process. It should also be noted that is preferred.

This is because chlorine is less corrosive and dangerous and is cheaper.

In the second step of the process), the halogen-containing polymer is removed from the halogen-containing solution, preferably free of residual condensation of the solution adhering to it, and then in the third step ( ) meets the following two essential requirements: (1) ability to penetrate halogen-containing polymers; and (1)
1) The polymer is brought into contact with a reagent or reactant that satisfies the ability to react with the elemental halogen in the polymer to produce a gas as one of the reaction products.

Suitable reagents are primarily reducing agents that reduce elemental halogens to halides, whereby the reagents used are oxidized to form one or more products;
At least one of the products is a gas at operating temperature and pressure.

The gas-generating reagents can themselves be gaseous, or they can be liquid, optionally in admixture with a suitable solvent.

Other gas-generating reagents are usually solids and are used in solution in a solvent.

As in the first step of the process, water is the preferred solvent in the third step.

Examples of gas-generating reagents suitable for use in the present method are nitrogen-generating reagents such as ammonia, ammonium hydroxide, hydrazine, nitric acid and nitrous acid, and carbon dioxide-generating agents such as formic acid and oxygen-generating reagents. Reagents such as hydrogen peroxide and its reactive derivatives, preferably in aqueous solution, and also reagents capable of producing sulfur dioxide, sulfur trioxide or hydrogen chloride, such as sulfurous acid and its salts,
hydrogen sulfide and its salts, and also reagents that produce hydrogen sulfide, such as mercaptans.

Ammonia (or ammonium hydroxide) and formic acid are preferred reagents.

This is because these are readily available, relatively inexpensive, and easy to handle.

The progress and completion of the third stage of the process can be understood by observing that the color of the polymer becomes brown and sometimes disappears due to the introduction of halogen into the polymer.

The reaction in this third stage solution was thus found to be relatively rapid and in many cases complete within minutes (subsequently confirmed by measuring the sorption capacity of the polymer). ).

For example, a sample of polyethylene terephthalate immersed in a saturated aqueous solution of bromine for 30 minutes will completely decolorize after being immersed in 25% aqueous ammonia for 20 to 60 seconds.

After the third cutting of the method is completed, the polymer is preferably removed so as not to come into contact with the gas-generating reagent and washed free of excess reagent and non-gaseous reaction products.

If necessary, the polymer is then dried in a conventional manner.

Microscopic examination of polymers treated according to the present invention shows the formation of multiple voids, bubbles and pores of various shapes within the polymer, some but not all of which are 1000 times larger. It is easily visible to the naked eye under magnification.

That is, a micrograph taken at 10.500x magnification of a cross section of the treated polymer shows numerous vertically elongated cylindrical voids;
These can also be described as microcapillaries.

Some of the voids extend to or almost to the surface of the treated polymer; in these cases the voids terminate either as open pores or as closed bubble-like protrusions.

It has also been found that a correlation exists between the density of voids formed in the polymers obtained as a result of this process and the increased sorption capacity of the polymers thus treated.

When ammonia is used as the gas-forming reagent, the density of the voids, that is, the number of voids per unit volume of the polymer, is determined by the amount of halogen added to the polymer in the first step (a) of the method and the number of voids per unit volume of the polymer. It has further been found that the concentration of ammonia in the aqueous solution with which the polymer is contacted in step 3 (c) is a function of both.

According to one embodiment of the invention, the third stage of the process is carried out at an elevated temperature, for example from 50 to 80<0>C.

Alternatively, the polymer can be subjected to elevated temperatures for a predetermined period of time after completion of the third stage of the process.

It has been found that in both of these cases the sorption capacity of the treated polymer is further increased as a result of heat treatment.

Without limiting the invention by theoretical reasons, the foregoing findings demonstrate that the advantageous results of the present method, namely the improved sorption properties of the treated polymers, are due to changes in the physical microstructure of the polymers. , suggesting that this is due to the increased or resulting porosity of the polymer.

The mechanism of these changes is envisioned as follows: The gas-forming reagent penetrating the polymer reacts rapidly in situ with the pre-elementary halogen contained in the polymer.

This reaction forms a considerable amount of LE gas, the pressure of which is often increased further due to the exothermic nature of the reaction.

As the gas expands, the formation of bubbles or voids is seen, and the bubbles or voids that reach the surface layer of the polymer can rupture to create open pores.

The fact that the sorption capacity of the polymer is further increased after heating the polymer according to embodiments of paragraphs 1j and 1j of the present invention is that the gas trapped in the closed voids or bubbles expands and the gas trapped in the closed voids or bubbles expands. This can be explained by the fact that some of the bubbles burst, thus increasing the number of open pores.

This explanation is substantiated by comparing micrographs (10,500x magnification) taken before and after applying heat to the treated polymer.

The novel process of the present invention is applicable to a wide variety of substantially hydrophobic thermoplastic polymers, including polyolefins (e.g. polyethylene, polypropylene, polyisobutylene and the like), substituted polyolefins (
(e.g. polystyrene, polyacrylonitrile, polyacrylate, polymethacrylate, polyvinyl chloride, polystyrene chloride, polytetrafluoroethylene), polyester (e.g. polyethylene terephthalate and the like), polyamide (e.g. polyhexamethylene aziboamide), polyimide (e.g. polycaprolactam),
Examples include, but are not limited to, cellulose esters (eg, cellulose triacetate).

There are also copolymers and terpolymers of the type mentioned above and other synthetic and natural polymers, elastomers and plastomers.

When using polymers that are potentially susceptible to chemical reactions or attacks due to pre-element halogens in the presence of light, such attacks can be reversed by It can be avoided by hitting the hill.

One example is polystyrene, whose aromatic nuclei undergo a light-promoted halogen substitution reaction, such as bromination with pre-elementary bromine.

The novel method of the present invention can be applied to virtually any of the above polymers in any desired physical form.

Said polymers can thus be in the form of fibres, filaments, woven or knitted fabrics, granules, powders, pellets, films, sheets, molded articles and the like.

As mentioned above, an important application of the present invention is synthetic fibers, yarns (
For dyeing yarn), textiles and sea 1.

Synthetic textiles, such as polyethylene, polypropylene or polyester (polyethylene terephthalate), are difficult to dye, especially with the aqueous disperse dye and basic dye systems widely used in other types of textiles. One thing is well known.

While polyethylene and polypropylene could previously be simply dyed, polyester required high temperatures and pressures and the use of a dye carrier to satisfactorily absorb the dye.

It has been shown that polyethylene, polypropylene and polyester fiber materials, for example, after they have been treated according to the invention, can be successfully dyed to deep shades with conventional aqueous disperse dye systems at relatively low temperatures and under atmospheric pressure. discovered.

Furthermore, it is not necessary to use dye auxiliaries to dye these treated polymers, although such auxiliaries can be used if additional coloring effects are desired.

According to another embodiment of the present invention, the improved sorption capacity of the polymer obtained by the present method is such that the improved sorption capacity of the polymer obtained by the present method makes it possible to sorb one or more substances selected from a variety of useful materials onto the polymer. It can be used for.

The substances to be sorbed can be gases, liquids or solids, and they can be sorbed by contacting them or their solutions or dispersions with the polymers treated according to the invention. It can be sorbed to coalescence.

Examples of substances that can be usefully added to polymers include fragrances, disinfectants, bacteriostatic agents, soaps, cleaning agents, pharmaceuticals, preparations, enzymes, deodorizers, humectants, water, oils, and clothing neutralizers. , explosives, poisonous gases, and magnetic metal powders.

Adding one or more reactants into the treated polymer and reacting them with another reactant (i.e. with each other) in sorbent form to produce a useful product, e.g. a disinfectant. You can also.

Similarly, monomer-catalyst systems can be added to the polymer to achieve polymerization of the monomers in the sorbed state.

On hydrophobic thermoplastic polymers that have not been treated according to the invention, many of the substances mentioned above are not sorbed at all, or even if some sorption occurs, the sorbed substances are retained by the untreated polymer. For example, it is lost by washing.

In accordance with, but not limited to, the mechanisms suggested above, it is believed that the sorbed materials are primarily introduced and retained within the pores or voids of the polymers treated according to the present invention.

This suggests that heating the polymer containing the sorbed substance can increase the retention of the sorbed substance by the polymer, which presumably closes the pores containing the sorbed substance. It also explains the facts.

The invention will be illustrated by, but not limited to, the following examples.

Example 1 Samples of undyed polyester (polyethylene terephthalate) knitted fabric of dimensions 20 cIrLX 20cRX O, 36 mm were injected into various aqueous solutions containing various concentrations of elemental chlorine and bromine as shown in Table 1 below. Soak at room temperature during the contact period.

The sample was removed from the halogen solution, briefly drained, and then incubated for 25 minutes until the sample was substantially decolorized (approximately 20 seconds).
Immerse in an ammonia aqueous solution of ~28φ.

The sample is then washed free of residual aqueous solution of ammonia and ammonium salts and air dried.

The thus treated sample of polyester textiles is then used for dyeing polyester textiles and BAS
"Paranyl Brilliant Lot BELJ" is a commercially available dye manufactured by Company F.
lliant Rot BEL).

1 hour at 100°C according to the dye manufacturer's instructions.
．． Dye the polyester textile sample at 5 concentrations (based on the textile).

The results of the dyeing experiments are shown in Table 1 below and are compared with those obtained using blank samples of similar textiles that were not subjected to treatment with halogens followed by treatment with ammonia according to the invention. It is.

Table 1 also shows that 0.6% of the conventional dye carrier "Levergal J", which was carried out according to the method described above, is recommended for use in dyeing polyester textiles.
The results of dyeing experiments carried out with g/11 added to the dyebath are also included.

The results in Table 1 clearly demonstrate the improved dyeability of textiles treated according to the invention.

The higher the concentration of chlorine or bromine in the treatment solution and the longer the contact time, i.e. the greater the amount of halogen added to the polymer in the first step of the treatment according to the method, the better the result. It is also found that the following can be obtained.

The data in Table 1 also shows that dye carriers can be usefully used to obtain further improvements in coloration.

Fabrics woven from the polyethylene films and polypropylene films of Examples 2-4 and also from small, unheated film ribbons (approximately 3 mm wide and 0.76 mm thick) of these materials were prepared substantially as described in Examples 2-4. 1 with an aqueous solution of bromine, followed by treatment with aqueous ammonia.

When these samples were observed under a microscope at 1000x magnification, they showed the formation of multiple pores that were not present in the untreated blank sample.

Then the dye rsam manufactured by Hoechst
The sample is dyed by immersing it in a dyebath containing 3 parts (based on the textile) of ``Aron Red BL'' at 90°C for 1 hour.

The results obtained are shown in Table 2 below.

Example 3 Samples of polyethylene terephthalate and polypropylene in yarn and ribbon form are treated according to the method of Example 1 with a saturated aqueous solution of chlorine at various pH values obtained by adding sulfuric acid.

The polypropylene sample was then dyed by the method of Example 2, and the resulting dye absorption rates are shown in Table 3 below.
It also contains data regarding mechanical strength, elongation and moisture content of all treated samples.

Moisture content is determined by conditioning the sample for 24 hours at 20° C. and a relative humidity of 65°C and then weighing the conditioned sample.

The sample is then dried at 105° C. for 1 hour to obtain the dry weight.

The polymers used were as follows: (i) Polyethylene terephthalate (polyester) 20CrILX 20c/nX 0.36cm before treatment, 0.39c/rL0 after treatment (11) Polypropylene yarn or woven bomb, unheated. Ribbon width 3.18mm x 0.76mm before processing, 0.80mm after processing, swatch 20crIL x 20
cm0 The results in Table 3 show that, inter alia, when the pH of the chlorine-containing solution is 0, the water content is increased compared to the results when the pH is 2.

The mechanical strength of the samples treated at pH 0 is somewhat reduced, but not to an unsatisfactory degree.

Example 4 Polyvinyl chloride (PVC) yarn is immersed in a 0.2 N aqueous solution of bromine for contact periods of 1-5 minutes, 30 minutes and 60 minutes.

Thereafter, the yarn is immersed in a concentrated aqueous solution of ammonium hydroxide for 20 seconds, thereby completely decolorizing the brown yarn due to bromine.

Next, using the third section's "Leverga plate" (see Example 1),
% (based on the textile) of paranyl "Bu IJ IJ Antrot".

When compared with a blank sample subjected to the same dyeing treatment, it was found that the dyeability of the PVC yarn treated as described above is clearly improved.

Example 5 A nylon yarn is subjected to the same treatment as described in Example 4, except that the aqueous concentration of bromine is reduced to 0.03N.

The results of the microscopic examination and the staining experiment are substantially the same as in Example 4 above.

Example 6 The method of Example 1 is repeated using the following samples: polyisobutylene sheet, polystyrene film, polyacrylonitrile fiber, triacetylcellulose film, polycaprolactam fiber, polyhexamethylene adipamide (nylon) yarn, polychloride. Vinyl yarn and polyvinylidene chloride yarn.

A series of four experiments were performed on each of the aforementioned samples using an aqueous solution of chlorine and bromine in the first step of the method of Example 1, and an aqueous ammonia and formic acid solution in the third step, respectively.
experiment.

Comparisons were made with untreated blanks in each case and Example 1
It was found that the polymer sample treated with this method showed improved dyeing properties when compared with a blank sample.

Example 7 A sample of the same polyethylene terephthalate knitted fabric as used in Example 1 is treated according to the method of Example 1 first with an aqueous solution saturated with bromine and then with an aqueous solution of ammonium hydroxide.

The samples are then immersed in water containing 1% musk oil dispersed therein and left in contact with the dispersion for 1 hour with continuous stirring.

The sample is then drained, rinsed with water and dried in air.

The knitted fabric sample obtained has a significant jacquard odor, which remains even after the sample is washed with a dilute solution of detergent and dried.

A textile blank sample is likewise immersed in an aqueous dispersion of musk oil without prior treatment with the bromine solution and with the ammonia solution according to the invention.

After washing this blank sample once with a dilute solution of detergent, it was found that the sample had lost all Jacora aroma.

Example 8 A sample of polypropylene textiles weighing 1 g is treated according to the method of Example 1 with a concentrated aqueous solution of bromine and then with aqueous ammonia.

The washed and dried sample was then washed with 25aA! 0,5.0% dissolved in 30% aqueous ethyl alcohol. ? of nitrofuryl-acrolein for 1 hour at 60°C.

The sample is then removed from the solution, washed with water and dried.

A blank sample of the same polypropylene fabric is similarly treated with the same alcoholic solution of nitrofuryl-acrolein, washed with water and dried.

Both samples according to this method and blank samples were analyzed for nitrogen content, with the blank sample showing O nitrogen, whereas the main sample previously treated with an aqueous solution of bromine and aqueous ammonia had a nitrogen content of 7%. It was found that it contains

2 of aminohydantoin dissolved in 50% methanol
The nitrogen-containing sample was immersed in the 8% solution for 1 hour.
Hold at 0°C.

Nitrofuryl-acrolein is found to undergo a condensation reaction with aminohydantoin under these conditions to form a fungicide.

The above-mentioned fungicide was used, for example, in the Soviet Union as ``furanone l'' (Fur).
agin).

Analysis of the nitrogen content of the sample obtained showed a nitrogen content of 10.4%, which is consistent with the formation of known condensation products when compared to the initial nitrogen content of 7%.

Example 9 A sample of a polyethylene terephthalate knitted fabric weighing 3 g is immersed in an 8φ aqueous solution containing sodium hypochlorite for 10 minutes at room temperature.

The sample is removed from the solution, drained, and immersed in 4 g of aqueous hydrochloric acid for 15 minutes while still wet with the hypochlorite solution.

Thereafter, the sample was taken out of the hydrochloric acid solution, drained, washed with water, and added to the ammonium hydroxide aqueous solution of sections 24 to 28.
Immerse for 0 seconds.

The sample is removed from the ammonium hydroxide solution, drained, rinsed with water, and air dried.

The resulting samples and also untreated blank samples were treated with 1-valanyl without dye carrier by the method of Example 1.
Stain with Brilliant Lot BELJ.

It was found that the dye uptake of the treated sample was four times that of the blank sample.

Example 10 A sample of organized polyethylene terephthalate was prepared at pH 2.
for 10 minutes at room temperature in a saturated aqueous solution of chlorine.

The sample is removed from the solution, drained, rinsed, and then immersed in an aqueous solution containing 5% sodium bisulfite.

The sample is removed from the bisulfite solution, drained, rinsed with water, and air dried.

The samples obtained and also the blank samples are stained as described in Example 9.

Substantially the same results as in Example 9 are obtained.

Claims (1)

[Claims] 1. A method for improving the sorption capacity of a substantially hydrophobic thermoplastic polymer, comprising the following steps: (a) chlorine, bromine, iodine, bromine chloride, iodine chloride and bromide; The polymer is brought into contact with a chemical solution containing an elemental halogen selected from the group consisting of iodine under conditions that avoid a chemical reaction between the halogen and the polymer. a first step of introducing the halogen; (b) a second step of removing the halogen-containing polymer from the solution; Contacting said polymer with a reagent consisting of ammonia, ammonium hydroxide, formic acid or sodium bisulfite capable of reacting with the elemental halogen contained in the coalescence to produce a gas as one of the reaction products. A method for improving the sorption capacity of a polymer, characterized in that it consists of a third step. 2. The method according to claim 1, in which the halogen is added in the form of an aqueous solution in step (a). 3 Claim 2 in which the pH value of the aqueous solution is O~3
The method described in section. 4. The above-mentioned polymer is potentially susceptible to the chemical reaction effects of the above-mentioned halogen in the presence of light, and the patent claims that steps (a), (D) and (c) are carried out in the dark. The method according to any one of Ranges 1 to 3. 5 Process (a) and ←→ at about 50℃ to about 80℃
The method according to any one of claims 1 to 4, which is carried out at a temperature of °C. 6 2 [degree (/→ the reagent used is ammonia 4=
? A method according to any one of claims 1 to 5. 7. The method according to claims 1 to 6, wherein the reagent used in step ←→ is dissolved in a solvent. 8. The method of claim 7, wherein said solvent is water. 9 Claim 1 in which the polymer is a polyolefin
~The method described in Section 8. 10 Claims 1 to 10 in which the polymer is polyester
The method described in any of Section 8. 11 Polymer is polystyrene, polyacrylonide IJ
Claims selected from polyvinyl chloride, polyvinylidene chloride, triacetyl cellulose, polymers thereof, terpolymers, graph 1 polymers, and block polymers The method described in Clauses 1 to 8. 12 Polymers can be used for films, sheets, fibers, yarns,
12. The method according to claims 1 to 11, wherein the method is in the form of a knitted fabric, a woven fabric, a non-woven fabric, or a granule. After the completion of step 13 (c), the polymer is
Claims 1 to 2 include an additional step of subjecting the method to a temperature of
The method according to any of paragraph 12.