KR0127095B1 - Proecess for preparing crysstalline spherical polyamide powder - Google Patents

Abstract

The crystalline single spherulite polyamide was prepared by the following steps 1) forming a transparent homogeneous solution by completely dissolving the block crystalline polyamide resin such as nylon 4, nylon 6 or nylon 6,6, etc. at high temperature in a phase separation solvent, 2) forming an opaque heterogeneous solution by phase separating the solvents such as glycerol, ethylene glycol, diethylene glycol, 2-butene-1,4-diol or their mixture, and the polyamide of the single spherulite by cooling at low temperature, 3) precipitating the separated polyamide by washing the solvent, 4) obtaining the independent crystalline single sperulite polyamide powder having 1- 100um of diameter polydispersities less than 1.10 by filtrating and drying the precipitates.

Description

Process for preparing crystalline polyamide spherical powder

1 is an electron micrograph of a polyamide spherical powder prepared according to the method of the present invention.

2 is an enlarged photomicrograph of a polyamide spherical powder prepared according to the method of the present invention.

3 is a polarization micrograph of a polyamide spherical powder prepared according to the method of the present invention.

Article 4 is a graph showing the size change of the polyamide spherical powder according to the concentration of the solution.

5 is a graph showing the change in size of polyamide spherical powder with cooling rate.

The present name is concerned with the cleaning of the formed polyamide spherical distribution on single single spherical tablets. To be further injured, the present invention provides a crystalline polyamide spherical form that obtains polyamide distribution on a dogwood win monocyte with uniform size distribution using a phase separation solvent that exhibits a nonsolvent or solvent benefit according to temperature of the bulk polyamide resin. This is how you know how to pay.

In general, vinyl-based thermoplastic resins synthesized by addition polymerization can be spherically entrained by emulsion polymerization in the polymerization process, but thermoplastic resins synthesized by condensation polymerization, such as polyamide thermoplastic resins, are bulked together and polymerized. Since it is possible to rinse in the middle of the distribution phase, it is the practice that adds separate distribution voting.

Conventionally, the method of rinsing powder, which is a common place of Goe's thermoplastic resins synthesized by condensation polymerization, is powdered into mechanical paper by using a superficial resin mill ball (b approx. .

However, the features of such a gymnastics method are to (1) lower the temperature of the glass glass transition temperature of the resin in order to crush the bulk resin into mechanical paper, so that a large rise of the washing tank is followed, and (2) the powder of the resin. The pressure is time-consuming, and (3) the productivity can be very low because the amount of deliveries that can be produced through one grinding process is less than several kilograms.

Therefore, due to the low acidity and high cleansing costs carried by these forgings, it is virtually impossible to put the mechanical chain method to practical use for mass production. In addition, the calvings which are gymnastic by mechanical grinding method have a polyhedral structure whose shape is irregular after the crushing, and the size distribution is so large that another separation process has to be added to obtain a desired sized separation plate. The escalation of tax costs and Sesanseong underground are inevitable.

The present inventors have studied to solve the problem of the method of cleaning the paper by the method of grinding the paper. As a result, the spherical shape of the polyamide can be obtained by using the nonsolvent and / or solvent benefit according to the temperature. It is possible to combine the first half, the acylol reversed the half name.

The purpose of the present invention is to fabricate a method for cleaning a binder-based polyamide resin spherical distribution having a uniform size distribution on the single-bulbing phase which can be counted as a future proof.

Lee and Gam are the people of this class.

(a) slowly dissolving the bulk crystalline polyamide resin in a solvent phase separation solvent at an excessive temperature to form a transparent homogeneous solution;

(b) cooling the homogeneous solution to geothermal to allow phase separation between the solvent and polyamide to form a transparent, homogeneous solution of the polyamide gamma-limin win monosphere phase;

(c) separating the boligamide as its relative relative to the base body by dissolving, washing and dissolving the mixed solvent solution for phase separation using a washing solvent;

(d) the precipitation rule was filtered and dried to obtain polyued powder distribution in a monolithic monolithic form with uniform size distribution.

The manufacturing process of the polyamide spherical powder to achieve the present wood of the present half is described in detail. The method of rinsing of this half is completely different from the conventional machine-crushing crime prevention method. A method of preparing a distribution having a uniform size distribution.

The crystalline polyaude resin used in the present invention includes nylon 4, nylon 6, nylon 7, nylon 8, nylon 9, silver 10, ninone 11, nylon 12, and nylon 6,6, nylon 7,7. , Nylon 8,8, nylon 6,10, nylon 9,9, nylon 10,9, nylon 10,10 and the like.

In general, the solvent / non-solvent method is a method of precipitating the resin of the coating and dissolving the resin by adding a transparent homogeneous solution, which is a cost-effective resin, to precipitate the dissolved resin. However, the shape of the sedimentary liquor obtained by adding the transparent homogeneous solution to the non-solvent to spread the solubility is ordinary oil, and its shape and size are more than hundreds of microns.

Therefore, the general delay solvent / non-solvent method is not only possible to make a uniform distribution of spherical distribution, but also in order to raise the final month of less than tens of urine. There is no great sign compared to the Hagi feunye machine paper bunkeman.

However, the gymnastic method according to this fame does not apply the solvent / non-solvent method, but the principle and the vacancy are fundamentally different. In other words, in the solvent / non-solvent, which is a general chuck, the precipitation of the oily or dispersible phase is obtained by using the difference of the resin solubility according to the composition of the solvent / non-solvent. Spherical powders are prepared by inducing the phase separation of homogeneous solution under a certain condition using a quality (hereinafter referred to as `` pH '' for phase separation) that acts as a solvent.

The solvent for phase separation used in the present example is to dissolve the polyamide resin at an excessive temperature to form a transparent homogeneous solution. On the other hand, when cold-coated, the phase separation between the solvent and the polyamide is induced to form a transparent, homogeneous solution in which the polyamide is phase separated into an independent monocyte phase. Thus, the solvent layer for phase separation is simply dissolved and washed by using a ball material (hereinafter referred to as a solvent for washing) that has excellent compatibility with the solvent for phase separation from the homogeneous solution in which phase separation has occurred, but is not compatible with polyamide resin. When washed, the polyamide is separated and phased as it is in phase separation. Filtration and precursor of this fibrous material lead to polyid distribution on monocytes with uniform size distribution. This is because the size of the delivered deliveries will affect the concentration and normal velocity of the solution, and if the size of the separated polyamide is uniformly adjusted by selecting the jigging concentration and cooling conditions during phase separation, The spherical powder of size can be raised in large quantities.

Fig. 1, Fig. 12 and Fig. 3 are electron micrographs, electron micrographs, and polarization micrographs of Sezowin polyamide spherical delivery, respectively.

Consideration should be given to the selection of the phase separation solvent. For example, when the melting temperature (referred to as Tm) of the polyanide is added to Chun, the non-solvent properties at temperatures below Tm-50 ° C, the properties of spalling at Tm_50t and above, and Tm + Above 30 tons, a clear, homogeneous solution should be formed. Doom ◀, room temperature should be more than 30cP. Third, the transparent homogeneous solution formed at high temperature must be phase separated into a cold culinary polydoid-docked single phase.

As a solvent for the constituents of this method, glycerol, ethenylene glycol, mayeteniglilin, 2-butene-1,4-diol, and mixtures and ear-conductors thereof may be used. It becomes unknown

Detailed description of the manufacturing process for the malleable polyamide bedding according to this nickname is given below. A polyamide resin in a weight ratio of 1% to 30% by weight in a phase separation solvent that satisfies the above mentioned conditions, preferably depending on the concentration and the cooling rate.

Figures 4 and 5 show the mean size variations of the separated win polyamide phases with concentration and cooling rate, respectively.

The concentration of the solution affects the rate of clarification of the polyamide, and the polyamide phase having a large concentration of solution can be lifted, and the size of the polyamide phase can be controlled in the range of 1 범위 to 100 坤. The average acidity yielding a size distribution is less than 1.10. In addition, the cooling rate can be lowered, but the local polyamide phase can be lifted up, but the change in size that can be controlled by the change in cooling rate is not more than 10 times. In addition, the density of the frozen polyamide phase can be adjusted by the example of solvent solubility, and the polyamide phase having a dense structure of freezing of the solvent is frozen. Although the mixture is completely mixed with the solvent for phase separation from the mixture after completion of normal phase separation, it is charged compatibility with copper amide, and only the phase separation solvent is dissolved, removed, dried and dried by using a solvent for application. The size and structure of the finely divided distribution is the same as the size and structure of the phase-separated boliamide phase in the cooling penalty, and each sphere is divided into single-walled tablets. Have

As a workmanship, it's probably not that we want to subdue this law.

Example 1

Preparation of Nylon 6 Spherical Powders

The mixture of 10% by weight of nylon 6 bulk resin in glycerin was dissolved in a stirrer of 2301C for about 30 minutes until nylon 6 was completely dissolved. Iringge melted mixing balls were cooled with cooling temperature control at 51C. This ice-cold example was phase-separated into Gailton 6 as an independent monocyte phase. This ringing phase-separated mixture was washed with only the bleach rate serine that is compatible with the rate serine. This is very important because the exchange rate of the three-time exchange rate is very important. Drying was performed to separate nylon 6 spherical distributions. The size and size distribution of the frozen spherical delivery can be domesticated using an electron microscope. In this example, the diameter of the spherical delivery of the spherical delivery was 20, the polydispersity representing the size distribution was 1.02.

Example 2

Washing of nylon 6,6 spherical powder

A mixture of 5% nylon 6,6 mass resin and 6 wt% of yeastene glycol was dissolved in a 230t stirrer for about 30 뷴 until the nylon 6,6 melted completely. The dissolved mixture was then cooled while controlling the cooling temperature to 10 t per minute. During this cooling, the nylon 6,6 were phase separated into the isolated single-bed phase. This phase-separated mixture was washed with Mulu etilangli corrugates compatible with etillianglyot. At this time, the exchanged centuries of the Egliangli Glial is very important, so wash it well three times or more and filter and dry to separate the nylon 6,6 spherical powder. The size and size distribution of the spherical distributions which have been raised can be confirmed using an electron microscope. In this example, the polymorphism of the frozen spherical distributions had a polydispersity of 8 / m and a polydispersity of 1.05.

Claims (7)

(a) dissolving the crystalline polyaulde resin superficially at high temperature in a solvent for phase separation to form a transparent homogeneous solution; (b) cooling the homogeneous solution to a low temperature to induce phase separation between the solvent and polyamide Forming a transparent transparent homogeneous solution in which polyamide is separated into an independent single bed phase (singlesphemlite); (c) removing the heterogeneous solution by dissolving, washing, and removing the solvent separation layer using a washing solvent. The amides are separated as phase separated relatives, and the quenching time is Danke; And (d) filtering and drying the QingZong ball to raise polyamide distribution on the dogwood win single crystal of uniform size main fabric. The method of claim 1, wherein the bulky polyamide resin is nylon 4, 'nylon 6, nylon 7, nylon 8, nylon 9, nylon 10, nylon 11, nylon 12, and nylon 6,6 nylon 7,7 And nylon 8,8, nylon 6,10, nylon 9,9, nylon 10,9, nylon l0,10. The solvent of claim 1, wherein the solvent for the main body exhibits the properties of the non-solvent at temperatures below Tm-501C based on the melting temperature of the polyamide (hereinafter abbreviated as Tm), and at higher temperatures. And manufacturing method of cut lead crystalline polyamide spherical powder having a clarity of 30 cps or more at room temperature. 4. The crystalline polyc according to claim 3, wherein the solvent for phase separation is glycerol from the group consisting of ethelial gold glycol, diemyl glycol, 2-butene-1,4-diol, and mixed and derivatives of the table. Gymnastic method of amide spherical delivery. The preparation of the crystalline polyamide spherical powder according to claim 1, wherein the washing solvent is not compatible with the solvent for separating the hem. The method for producing a crystalline polyamide spherical main pressure according to claim 1, wherein a range of 1 μm to 100 / mm 3 of the local diameter of the spherical distribution is 1.10 or less in a polydispersity diagram representing the size distribution. The method of claim 1, wherein in step (a), the bulky crystalline polyamide resin is added at 1% to 300% by weight of solvent for phase separation, and in step (b), the transparent homogeneous solution is prepared at a rate of 0.1 ° C to 2 ° C. The cooling time is a method for producing a crystallized popriamide sphere.