JPS59199722A - Improvement of plasticizer absorbability of plastisol type polyvinyl chloride and resin obtained thereby - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to plastisol type resins, particularly plastisol type resins having excellent plasticizer absorption capacity.

Generally, two types of polyvinyl chloride resins are available for industrial use. These include multi-purpose resins with fairly large particle sizes, for example from about 25 to 220 microns; and plastisol-type resins with very small particle sizes, for example from about 0.1 to 0.0 microns. Multi-purpose resins tend to be porous and can therefore easily absorb plasticizers; as a result, the resins are used in dry blend production, which is a free-flowing powder consisting of resin granules treated with plasticizers. be done.

On the other hand, plastisol-type resins (also called dispersion-grade resins) have extremely small pores and, as a result, have virtually no ability to absorb plasticizers. Although there is a need for small particle size resins that exhibit relatively high plasticizer absorption capacity, Applicant is not heretofore aware of the existence of such materials.

Therefore, an object of the present invention is to provide a plastisol type resin having excellent plasticizer absorption ability.

Another object of the present invention is to provide a simple process for processing currently available plastisol type resins to provide low cost, fine particle size resins with high plasticizer absorption capacity.

It is a further object of the present invention to provide small particle size, high plasticizer absorption materials useful for example in binder systems, fluid bed applications, powder coating systems, and vinyl stencils used in the manufacture of resilient floor coverings. Our goal is to provide resin. These and other objects of the invention will become apparent from the following detailed description of the preferred embodiments.

The present invention relates to a method for treating sol-type polyvinyl chloride resins with small particle size and relatively low plasticizer absorption capacity in order to improve the plasticizer absorption capacity of the resin. The method treats the resin granules with water at a temperature of about 66° C. (15° F.) or less for a time sufficient to enhance the plasticizer absorption capacity of the resin.

In a first preferred embodiment, the invention relates to a method for improving the plasticizer absorption capacity of plastisol-type polyvinyl chloride resins, the method comprising the steps of selecting a suitable plastisol-type polyvinyl chloride resin and introducing the resin into a fluid medium. heating at a temperature below about 65.5° C. (150 F.).

In a second embodiment, the present invention relates to a treated plastisol type polyvinyl chloride resin having a superior plasticizer absorption capacity compared to an untreated resin, wherein the treated resin is a fluid containing a suitable plastisol type polyvinyl chloride resin. Approximately 6 in the medium
Obtained by heating at a temperature of 5.5°C or lower.

In a third embodiment, the present invention relates to a converted plastisol-type resin comprising an imbibed plasticizer, wherein 1° the resin is prepared by converting a suitable plastisol-type polyvinyl chloride resin in a fluid medium at a temperature below about 655°C. ) by heating and exposing the resin to be converted to a suitable plasticizer.

The resin to which the present invention is applicable consists of polyvinyl chloride homopolymer and copolymer plastisol type resins. Although the majority of commonly utilized plastisol-type resins are produced by emulsion polymerization methods, other methods, such as micro-suspension methods, are also used in the production of these resins. The method of making the resin is not believed to be important for purposes of the present invention. Furthermore, the nature of the ultimately absorbed plasticizer is not very important since almost all of the plasticizer used is absorbed by the resin once it has been converted.

Typical plastisol type resins generally have a particle size of 5 microns or less in diameter. And this type of resin is desirable for the practice of this invention. However, the invention can also be carried out with larger particle size resins, for example 12μ or 25μ. The term "plastisol type" as used herein refers primarily to the particle size of the plasticizer, but rather to the inability of the resin to absorb the plasticizer. Plastisol-type resins (5) Although in some cases have fairly large particle sizes, they have a low capacity for absorbing plasticizers when compared to, for example, multi-purpose resins. Accordingly, the present invention relates to resins suitable for exhibiting high plasticizer absorption when processed as disclosed. For convenience,
Traditional plastisol type.

Since only the resin in the distributed group 1 node was successfully converted,
They are called "plastisol-type resins." Multi-purpose resins with large particle sizes range from 160-220μ to 35-5μ
It has been found that even if the particles are pulverized to a particle size of about 0 μm, they are not affected when treated according to the present invention.

Although both homopolymer and copolymer plastisol resins were successfully processed according to the present invention, some differences were observed between the two resins.

Copolymer resins appear to convert more easily than homopolymer resins, thus at lower temperatures. Homopolymer resins, on the other hand, exhibit conversion trends that may be related to differences in molecular weight and glass transition temperature. For example, homopolymer resins with high molecular weights and high glass transition temperatures generally require higher water temperatures for conversion than copolymers with relatively low molecular weights and low glass transition temperatures. Homopolymer resins treated according to the present invention have approximately 7o, oo.

~120. It had an average molecular weight of OOO. And the conversion temperature increased with increasing molecular weight. On the other hand, although almost all of the copolymer resins treated according to the invention had molecular weights in the higher end of the range, they all exhibited relatively low conversion temperatures.

The reason for these differences is unknown.

To practice the present invention, a suitable plastisol-type resin is heated in an all-fluid medium for a period of time sufficient to enhance the absorption capacity of the resin. Preferably, the fluid medium consists of water, but air or liquids that are solvents for the resin at the given temperature are also possible. In reality, the liquid consists of water and (t7'j) an organic liquid.

Although fluid media other than water are possible, there are certain drawbacks to the use of such media. Air can support conversion at high temperatures, but results in highly agglomerated products. Bulk substitutes are difficult to handle and, as a result, air is less attractive than liquid media. However, not all liquid media are satisfactory. For example, organic liquids pose health and environmental concerns and result in loose clumps.

It is well known in the art that polyvinyl chloride resin particles can be solvated and/or plasticized by certain organic liquids. When such liquids are used in the practice of this invention, highly agglomerated products can be obtained. In the most severe cases, agglomeration causes the resin to lose its particulate character. In many cases, comminution is effective in separating loosely agglomerated particles to produce an acceptable product. However, to minimize agglomeration problems, it is desirable that the liquid medium be unable to substantially solvate or plasticize the resin particles under the processing conditions.

For the aforementioned reasons, the use of water as the fluid medium is most desirable, and most of the discussion and comments herein relate specifically to water. When using water, the resin sample is placed in a volume of water and heated. It has been shown that the relative proportions of the materials do not significantly affect the rate of change, although a ratio of about 10 parts water to 1 part resin generally gave satisfactory results.

It turns out that in almost all cases the time required for conversion is inversely proportional to the temperature of the water. The minimum temperature required appears to be about 65°C. And the rate of change is the temperature when the boiling point of water (100
It accelerates as the temperature rises to ℃). In most cases, about 8
30 minutes at a temperature of 2°C gave suitable results, but as mentioned above, this depends on the nature of the resin, molecular weight and/or glass transition temperature.

Often the point at which the change occurs is visible to the naked eye.

For example, when a resin sample was heated with water in a flask at a temperature of 82 °C with magnetic stirring, the conversion point was detected by a change in the stirrability of the resin, i.e., the resin was initially easy to stir and was easily dissolved in water. However, after conversion, it tended to remain at the bottom of the flask despite the stirring action. In some cases, one particle floated to the surface of the conversion effluent.

The absorption of the plasticizer into the converted resin particles takes place either while the converted resin (9) resin is in contact with the liquid medium or after it has been separated from the liquid medium. However, if the plasticizer can be added while the resin is in contact with the liquid medium, it is desirable, and in most cases necessary, to convert the resin before adding the plasticizer. As aforementioned,
This is because the unconverted resin, medium and plasticizer form a lump of material that is difficult to handle when mixed.

A number of physical measurements were performed on treated and untreated samples. These measurements include absolute density, median pore size,
It was shown that the cumulative pore volume absorption and the treated and untreated samples were the same.

On the other hand, the average particle size of the treated sample was about twice that of the untreated sample, and the specific surface area seemed to decrease slightly.

Changes in rheology and physical measurements suggest that the change in absorption properties is due to a change in the surface properties of the resin particles and not to a change in physical properties. This change appears to be permanent. No evidence has been found to suggest that it is temporary in nature. Substantially all B(10) lastisol type resins are of the ASTM D-136
6, but shows an increase in the absorption of plasticizer according to 2. The resin is not converted. Therefore, in carrying out the present invention, care must be taken in selecting an appropriate plastisol type resin.

The contributions and advantages of the invention will become apparent from the following examples, which are illustrative and not intended to be limiting.

Example 1 PVC (polyvinyl chloride) copolymer dispersion resin (Tenn
eco 0565 resin) 1255+.

Added with stirring to 1000+ il of deionized water heated to 49°C (12oF) and 82°C (180F), respectively. Each sample was stirred at the altitude for 30 minutes, filtered through a Buchner funnel, spread on kraft paper, and dried at ambient temperature for 24 hours.

Each dried sample was placed in a Mixmaster (Mixma
ster) blender to mix 55 parts by weight of dioctyl phthalate, 5 parts by weight of Admex 710 plasticizer/stabilizer, and 1 part by weight of Mark 275 tin stabilizer (the amount of resin was 100 parts by weight). The additional additives in this and the following examples were added to the resin post-treatment bath and had little or no effect on plasticizer absorption. While the sample heated at 119°C produced a typical plastisol with a pull-through viscosity curve of 700 cps, the sample heated at 82°C absorbed the plasticizer and produced dry resin instead of typical plastisol. generated.

Example 2 The method shown in Example 1' (5PVC homopolymer monodispersed resin (
Tenneco 1755 resin). After the resin was separated and dried as described in Example 1, each sample was treated with the same amounts of dioctyl phthalate, AbimexF 10 plasticizer/stabilizer, and Mark 275 tin stabilizer in the proportions described above. The sample heated at 19°C produced a typical plastisol with a Pulckfield viscosity of 35°C, while the sample heated at 82°C produced a dry solid material.

Example 5 This example illustrates various methods of plasticizing resin samples after conversion to absorbable form according to the present invention. In each case, 175I of Tenneco O565 dispersion resin f was heated in 1200 ml of water, followed by 26.2 g of dioctyl phthalate and 16 g of epoxidized soybean oil stabilizer.
．． 99, o, 8y, and a stabilizer consisting of Symptron 11133. Sample 3DQ
All samples except one were heated for 30 minutes at 82°C.

Sample '5A was cooled to 52°C and suction filtered through a Buchner funnel, then spread on Kraft paper and dried for 118 hours. The sample was transferred to a Mixmaster mixer, the plasticizer mixture was added over 5 minutes with low speed stirring, and the resulting mixture was stirred for an additional 5 minutes. As a result, a dry powder was obtained.

Sample 3B was also cooled to 32°C, but the plasticizer mixture was then added to the water mixture with stirring over a 5 minute period. After stirring for an additional minute, the resin was filtered and dried as described in Example 1. A dry powder was obtained.

There was no unabsorbed plasticizer in the filtrate. When the resin was extracted with diethyl ether, it was found that 2 of the absorbed substances
It was found that 0.5% by weight could be removed.

Sample 3C was processed in substantially the same manner as Sample 5B except that the plasticizer mixture was added to the water while it was at 82°C. A similar resin sample was obtained from which 19.
) 1% by weight of absorbed substances could be extracted.

Sample 5D was prepared for comparison purposes to demonstrate that it is advisable, and perhaps necessary, to convert the resin before adding plasticizer. The plasticizer mixture for this sample was added in a conventional manner to a water slurry of untreated resin at room temperature. The resulting mixture could not be agitated and did not produce the fine powder normally obtained by the present invention.

Example 4 This example demonstrates the excellent plasticizer absorption capacity of various plastisol-type resins heated for 30 minutes (14) at the indicated temperatures in accordance with the present invention. Measurement of plasticizer absorption is performed using ASTM D-1'+6
A plasticizer absorption test was conducted using a slightly modified version of 6 using the dioctyl phthalate plasticizer.

These resins are all emulsion polymerized resins except Lucovyl resin, which is a fine suspension polymerized resin.

PB1702 Pou Lenc H93,38
6,2DR-600Goodyear H9g, g
6u03CC-NV2 5tau, ffer
H9E! , 8 71↓, 9Geon 1g+1
Goodrich H9 U 7
381755 Tenneco H8
2,2IIroFT'C-6ro37 0cciden
tal H93U 9070565
Tenneco C82269,1FPC-
63380cci, dental C82,270
, 2 Example 5 This example shows the effect of temperature on plasticizer absorption for samples heated at various altitudes. Measurement is 8 STMD-1366
This was done through a plasticizer absorption test with a slightly modified version. The resin used for all samples was Tenneco O565 copolymer dispersion resin.

The heating of each sample was then maintained for 50 minutes.

First control sample Washed with water at room temperature Heated at 1188°C Heated at 60°C Heated at 71.1°C 768
Heat at 822°C 691 Spray drying using a Bowen conical spray dryer, feed rate 5.11 KDa/hr, inlet air? The crystallinity was 177°C and the outlet air temperature was 79°C. The bulk density was measured for the initial control sample and the sample heated at 82.2°C, and was 0.55! j7'
The bulk density was 0221↓g/crd.

Comparative tests were conducted on samples of Tenneco 1775 homopoly-7-PVC resin with the following results.

Initial Control Sample Heated at 60°C Heated at 71.1°C Heated at 82.2°C '18.3 Example 6 This example describes physical measurements performed on treated and untreated samples of Tenneco 0565 copolymer resin. .

(17) Results Feed material density (g/CC) 1. U9 1 U9 Average particle size (μm) 1.6
:1. '4 Specific surface area (m"/g) 2.I
L 2.1 Cumulative pore volume absorption (CC/g)
0.005 0.003 Median pore diameter (μm) 0.0011 The feed density measured by the O,001 + helium replacement method and the median pore diameter measured by the mercury intrusion method did not change, but the specific surface area and Cumulative pore volume absorption (both measured by BET gas absorption method) decreased slightly. The mean diameter (measured by gravity sedimentation method) increased approximately twice. Overall, these data suggest that the change in absorption is due to a change in the surface properties of the resin particles.

Example 7 This example illustrates the ineffectiveness observed when a multi-purpose resin sample was treated according to the present invention. The resin used is Vyg
The multi-purpose resin, which was en 310, had a particle size of 220 μm. One sample was used as is (18) and the second sample was ground to an average particle size of 50 μm using a grinder. Plasticizer absorption of these samples and samples treated with water at 93.3° C. according to the present invention was determined using ASTM D-1366 with slight modifications.
The results are as follows: Vygen 310 +↓11.
5V'Ygen 310 (50μm)
+1311 processed Vygen 510
1114.2 treated Vygen
310 (50 μm) 14118 These results indicate that the plasticizer absorption of this multipurpose resin sample is not affected by water treatment according to the present invention.

Example 8 This example shows the results obtained when converting using different liquid media and temperatures. Tennec.

Samples of 0565 were prepared using ethanol or ethanol/water (1
:1) to the temperatures shown in the table below.

Ethanol/water (1:1) lI 8g65,5
63.1↓ Ethanol lIg, 8 65, 5 62.9 These results indicate that the conversion takes place in a medium other than water.

The present invention is not limited to the above description and explanation;
It includes all contemplated changes in the scope of the claims.

Claims (1)

[Claims] L (a) selecting a suitable plastisol-type polyvinyl chloride resin; and (b) heating said resin in a fluid medium at about 66°C (1
A method for improving the plasticizer absorption ability of a plastisol type polyvinyl chloride resin, which comprises a step of heating at a temperature of 50F) or lower. 2. Superior plasticizer absorption capacity compared to untreated resins obtained by heating suitable plastisol-type polyvinyl chloride resins in a fluid medium at temperatures below about 66°C (150F). Plastisol type polyvinyl chloride resin to be treated. C. Obtained by heating a suitable plastisol-type polyvinyl chloride resin in a fluid medium at a temperature of about 66°C (15oF) or less, and then exposing the resin converted by the heating to a suitable plasticizer. A converted plastisol-type resin consisting of an absorbed plasticizer.