JPH0131778B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the crosslinking or curing of chlorine-containing polymers with amine-containing crosslinkers. An important use of vinyl chloride polymers is as a binder for nonwovens, such as paper impregnation agents in making paper for air or oil filters. The filter, which is combined with a vinyl chloride polymer impregnant and pleated, should be resistant to delamination and tearing. Another requirement is wetting strength. One of the problems with the use of chlorine-containing emulsion polymers such as vinyl chloride during saturation of fibrous substrates is the need to increase the physical properties, particularly the wetting strength of the polymer. That's true. In the past, melamine in emulsions -
Addition of formaldehyde resin has been used to improve the wetting strength of the polymer. The resulting composition produced adequate wet strength, but a brittle product with poor flexural strength was obtained. The delamination resistance of the impregnated fibrous matrix was also poor. Additionally, the formaldehyde content of resins has been opposed in the industry because of its potential toxicity and because it requires high temperatures to obtain optimal properties. It is also known to improve the properties of vinyl chloride polymers by cross-linking them with linear aliphatic polyamines such as polyethyleneimine. U.S. Pat. No. 3,410,811 states that at least 100°C
The vinyl chloride resin is reacted with ammonia or an aqueous solution of aliphatic mono- and polyamines having less than 13 carbon atoms per molecule at a temperature of
A granular, polyvinyl chloride-based anion exchange resin is disclosed which is prepared by further reaction with this polyfunctional compound having amine-reactive groups. US Pat. No. 3,833,531 and US Pat. No. 3,968,317 are representative of techniques that demonstrate the reaction between sialylamine polymers and epihalohydrins, such as epichlorohydrin. US Pat. No. 4,167,610 discloses reacting an allylamine type polymer with an organic dihalo compound to obtain an ion exchange resin. The present invention provides a binder composition for a nonwoven fibrous substrate comprising a chlorine-containing polymeric binder and an amine crosslinker that is a specific polyamine polymer containing a 5- to 6-membered N-heterocyclic moiety. It provides: The above-described binder composition, when applied to a nonwoven web of fibers and cured, provides the following advantages: No self-condensation of the crosslinker, as is the case with melamine-formaldehyde crosslinkers. The formation of brittle matrices can thus be avoided, resulting in a relatively flexible product; The cross-linking reactivity of the amine polymer due to the piperidine or pyrrolidine group moieties results in curing at relatively low temperatures; The pleated paper combined with the binder composition provides a relatively high cross-link density resulting in increased chemical resistance, is resistant to delamination and splitting, and has enhanced wetting properties. Shows strength. According to the present invention, there is provided a nonwoven binder composition that can be used as a paper impregnating agent in the manufacture of paper and air and oil filters in which the main component of the binder composition is a chlorine-containing polymer. Ru. 5 or 6
By combining the chlorine-containing polymer with up to about 25% by weight of polyamine polymers containing N-membered heterocyclic groups, ie, pyrrolidine and piperidine moieties, the properties are improved. The amine polymer has the formula (In the formula, R is hydrogen or a C ₁ to C ₄ alkyl group,
R' is hydrogen or a methyl group) by polymerizing at least one diallylamine. Examples of diallylamines of the above formula are 2,2'-dimethyldiallylamine, 2,2'-diethyldiallylamine, 2,2'-dipropyldiallylamine,
2,2'-diisobutyldiallylamine, N-methyldiallylamine, 2,2'-dimethyl-N-methyldiallylamine, 2,2'-diethyl-N-methyldiallylamine and diallylamine, which are the preferred monomers for the polymerization. ). Diallylamine polymers are known in the art, as are methods of making them. US patent
See 2926161 and 3700623, which are incorporated by reference. The diallylamine polymer produced contains units of the following formula: as well as (wherein R and R' are as defined above). These formulas represent the pyrrolidine and piperidine moieties, respectively, of the polymer. Piperidine is believed to be the predominant N-heterocyclic moiety in the polymer. It is preferred to use poly(diallylamines) of high molecular weight, ie from about 70,000 to 120,000. Additionally, copolymers of diallylamines with up to about 40% by weight of copolymerizable monomers such as vinyl acetate are also suitable. In preparing the binder composition of the present invention, up to about 25% by weight, preferably from 1 to 10% by weight, of diallylamine polymer is mixed with the chlorine-containing polymer emulsion (on a solids basis). Polymer emulsions suitable for carrying out the invention include vinyl chloride homopolymers and copolymers, especially vinyl chloride-ethylene copolymers containing from 5 to 35% by weight of ethylene, vinylidene polymers and chlorine acrylic polymers. Although any procedure known in the art for producing the above-mentioned polymers can be used, it is preferred to use chlorine-containing polymers that are readily commercially available. The chlorine-containing polymer emulsion and the 5- and/or 6-membered N-heterocycle-containing amine polymer are simply blended in the proportions described above and applied by application methods well known in the art, such as spraying, dipping, and printing.
It is applied to a nonwoven web of synthetic or natural fibers, such as polyester or cellulosic fibers, in an amount of 80% paper solids by weight. Because of the relatively high reactivity of the N-heterocyclic moiety with the chlorine atoms in the chlorine-containing polymer, cross-linking of this polymer composition can occur at room temperature, but the cross-linking and curing effects are It can be carried out at temperatures in the °C range. Other ingredients that can optionally be included in binder compositions for nonwoven products include surfactants and pigments typically used in the art. The following examples merely illustrate and do not limit the invention. Example 1 This example shows the homopolymerization of diallylamine.
Deionized water (300 g) and diallylamine (300 g) were added to a 1 liter beaker under stirring generated by a magnetic stir bar. Until a pH of 2.0 is reached.
Concentrated sulfuric acid was added to this mixture. Reduce the percent solids to 40% by adding water (150g) and PH
Readjusted to 2.0. The mixture was transferred to a 1 liter water jacket reactor and purged with subsurface nitrogen for 30 minutes. During this time, the mixture was stirred at 200 rpm using a mechanical stirrer. Then increase the agitation to 300 rpm and 5%
Polymerization was started and maintained at 55° C. using delayed addition (incremental addition over a period of time) of a redox system consisting of aqueous hydrogen peroxide and 10% aqueous sodium formaldehyde sulfoxylate. When the isotherm dropped, the addition of the redox system was stopped and at this time 60 ml of 5% hydrogen peroxide and 80 ml of sodium formaldehyde sulfoxylate had been added. The cooled reaction mixture was adjusted to pH 12 with potassium hydroxide.
And so. The free diallylamine polymer separated as a viscous upper layer that was decanted, washed with water, and then purged with air to remove residual monomer. EXAMPLE 2 The diallylamine polymer of Example 1, polyethyleneimine (acrylic), and melamine-formaldehyde crosslinker were prepared based on a copolymer commercially available from Air Products and Chemicals, Inc. It was compared as a cross-linking agent for Airflex-4514 polymer emulsion, a vinyl chloride-ethylene copolymer of 50% solids and 20% ethylene. The various crosslinkers were blended with the vinyl chloride-ethylene copolymer emulsion at a level of 5% by weight on a dry basis. This blended composition was then applied with a Teflon sheet and cured.
Unconstrained films were tested for swelling coefficient (% solvent swell/% dry) and % solvent insolubles by solvent immersion or Soxhlet extraction. It can be seen from Table 1 that the diallylamine polymer cross-linked composition exhibited a much lower swelling coefficient than the other compositions, indicating a much higher cross-link density of the cured composition. Similarly, the higher insolubles values obtained with diallylamine polymer-containing compositions clearly indicated that there was higher cross-linking.

Table: PEI-12 is a polyethyleneimine sold by Aceto Chemical Company. Regimen 841 is a melamine-formaldehyde marketed by Monsanto Corporation. DMF = dimethylformamide THF = tetrahydrofuran In addition, the solvent resistance of the three cross-linked vinyl chloride-ethylene copolymers was determined by contacting the polymer film with the solvent for 3 minutes and abrading the solvent-soaked film using a wooden tong depressor. The evaluation was made by The second shows that the diallylamine polymer-containing compositions produced films that clearly exhibited relatively greater resistance to solvent attack.

[Table] Enryo
Vinyl chloride-ethylene copolymer emulsion,
diallylamine polymer, polyethyleneimine and its mixture with melamine-formaldehyde,
Applied to commercially available filter stock, 300〓
It was cured for 7 minutes at 100 ml and evaluated as a paper saturant at the 10% solids level.

Table 3 The data in Table 3 show that the diallylamine polymer-containing composition outperformed the polyethyleneimine-containing composition in all impregnation properties and outperformed the melamine-formaldehyde-containing composition in the MIT fold and Scott bond tests. Show that you are in a good position. The MIT Fold is a measure of bending strength and the Scott Bond test indicates resistance to delamination. Unfortunately, caustic soda lowers the pH to about 11.
Unless adjusted to
The vinyl chloride-ethylene copolymer emulsion is coagulated. This binder composition has such high
Since it was used in PH, much of the impregnation data using the polymer of Example 1 is probably lower than what would be obtained otherwise. Caustic soda is
It reduces the strength of the paper and impairs its water resistance. Two samples of diallylamine polymer prepared according to Example 1, a low molecular weight polymer and a high molecular weight polymer, with degrees of 10 cps and 19 cps, respectively, at a solids content of 23% were prepared by air products.
Airflex-4530, a vinyl chloride-ethylene copolymer emulsion containing 50% solids and 12.5% ethylene on a copolymer basis, marketed by And Chemicals, Inc.

Table 4 shows that low levels of low molecular weight and high molecular weight diallylamine polymers both produced significant improvements in the properties of the binder composition compared to a vinyl chloride-ethylene emulsion without a crosslinker. shows. Example 3 In this example, a vinyl chloride-ethylene copolymer prepared in the presence of polyvinyl alcohol as a protective colloid was mixed with various cross-linking agents. This copolymer is approximately 77% vinyl chloride, 18
% ethylene and 5% polyvinyl alcohol.

【table】

Table: Glyoxal 40 is a glyoxyaldehyde sold by Union Carbide. Cicart 4040 is p-toluenesulfonic acid sold by American Cyanamid. When used with polyvinyl alcohol/vinyl chloride-ethylene copolymer emulsions, diallylamine polymers exhibited better dry tear and murene burst strength than melamine-formaldehyde. MIT Fold and Scots Bond are
The results were better in the case of diallylamine polymer. Melamine-formaldehyde crosslinker 13
It should be noted that only 4.8% by weight of diallylamine polymer was used. The present invention provides mixtures of chlorine-containing polymers and up to 25% by weight N-heterocycle-containing polyamines as binders for nonwovens.

Claims (1)

[Scope of Claims] 1. A chlorine-containing polymer consisting of a vinyl chloride homopolymer, a vinyl chloride copolymer, a vinylidene chloride polymer, or a chlorinated acrylic polymer, and 25% by weight
1. A binder composition for nonwoven fabrics comprising an amine polymer as a cross-linking agent in an amount of up to (In the formula, R is hydrogen or _{a C1-4 alkyl} group,
A binder composition for nonwoven fabrics which is a polymerization product of at least one diallylamine (R' is hydrogen or a methyl group). 2. The binder composition according to claim 1, wherein the amine polymer contains a pyrrolidine or piperidine group moiety. 3. The binder composition according to claim 1, wherein the amine polymer is poly(diallylamine). 4. A composition according to claim 1, wherein the amine polymer is present in an amount of 1 to 10% by weight. 5. The binder composition according to claim 1, wherein the chlorine-containing polymer is a vinyl chloride/ethylene copolymer.