CN108003373A - A kind of method that colored expandable polystyrene particles are prepared by expandable polystyrene particles - Google Patents

Abstract

The invention relates to a method for preparing colored expandable polystyrene particles from expandable polystyrene particles. The method is to add polystyrene particles into a mixed solvent containing dye and stir to make the polystyrene particles swell, and the dye Entering the swelling space of polystyrene particles, the mixed solvent volatilizes to obtain colored polystyrene particles. The invention uses few reagents for preparing colored polystyrene particles, simple process, uniform internal dyeing of polystyrene particles, and low preparation cost, and can effectively solve the problem of polystyrene single color, dye polymerization inhibition and suspension polymerization of colored polystyrene. Directly dyeing the inside of expandable polystyrene particles cannot be colored.

Description

A method for preparing colored expandable polystyrene particles from expandable polystyrene particles method

technical field

The invention relates to a method for preparing colored expandable polystyrene particles, in particular to a method for preparing expandable colored polystyrene from expandable polystyrene.

Background technique

Expandable polystyrene is mostly used in the production of construction, packaging and decoration materials due to its low density, softness and easy processing. At present, my country has a large demand for polystyrene products, and the output of expandable polystyrene produced with styrene as raw material has leapt to the second place in the world of foam plastics. However, polystyrene raw materials are mostly white, and a single color will also limit the scope of use of packaging materials. Therefore, it is urgent to develop a preparation process of a simple and low-cost colored expandable polystyrene raw material to meet the needs of social life, enrich people's lives and delight people's mood, and add luster to life.

There are many ways to prepare colored expandable polystyrene particles. Chinese patent CN102875713A discloses a color expandable polystyrene resin and a method for preparing the color expandable polystyrene resin in one step. The method is to directly add organic dyes in the later stage of the polymerization reaction to obtain colored expandable polystyrene, which solves the compatibility problem between dyes and oily polystyrene. Since this method is prepared with styrene monomer, it needs to be added in the reaction Dispersant, initiator, plasticizer, surface coating agent, electrostatic precipitant and other components. But its shortcoming is: also add various reagents such as dispersant, initiator, plasticizer, surface coating agent, electrostatic precipitant during reaction, make cost increase, and the addition time of dyestuff is difficult to control accurately. Added reagents can affect the polymerization reaction.

Chinese patent CN102719031B discloses a color expandable polystyrene resin bead with high color strength and high light fastness and a preparation method thereof. In this method, the organic pigment is ground first, and finally washed with hydrochloric acid and deionized water. In this method, surfactants and dispersants are added during the reaction process, which makes the system more complicated, and the addition of materials such as pigment paste will affect the stability of the polymerization system. In addition, this scheme will be completed in three steps, and the last step is also used Acid and deionized water washing, the process is cumbersome.

Chinese patent CN105713310A discloses a preparation method of polystyrene EPS color resin board. The method is to use raw materials such as EPS and water-based coloring material to prepare colored EPS resin plates. The raw material is polystyrene, and the water-based coloring material is used for its poor compatibility, and polystyrene can only be colored on the surface. When the expandable polystyrene particles are directly dyed with water-based colorants, the inside of the polystyrene particles is not easy to be dyed because the colorants are not easy to penetrate and diffuse into the interior of the polystyrene particles. However, in the preparation of this method, the compatibility between the water-based pigment and EPS is poor, and problems such as uneven dyeing may occur. In addition, the use of various toughening agents, fillers, crosslinking agents, accelerators, and reinforcing agents greatly increases the cost. To sum up, the above-mentioned existing methods have the problems of many types of reagents and cumbersome processes.

Contents of the invention

The object of the present invention is to provide a method for preparing colored expandable polystyrene particles from expandable polystyrene particles to address the deficiencies of the prior art.

The purpose of the present invention is achieved through the following technical solutions:

A method for preparing colored expandable polystyrene particles from expandable polystyrene particles, specifically comprising the following steps:

A. At room temperature, add toluene, alcohol solvent and 1 to 10 g of organic dyes to a three-necked flask connected with a condenser tube and a mechanical stirrer in sequence, and stir for 10 to 30 minutes at a stirring speed of 100 to 180 r/min to obtain Contains organic dye solutions;

B. Add 80 to 100 g of expandable polystyrene particles to the solution containing organic dyes obtained in step A, and at a stirring speed of 100 to 180 r/min, the stirring time is 60 to 120 min, and a liquid level gauge is prepared. When the liquid level of the solution is lower than the liquid level gauge number, add toluene solvent to the liquid level gauge number;

C. After 1-2 hours, add the same alcohol solvent as in step A and continue stirring for 10-20 minutes. After filtering and drying, colored expandable polystyrene particles are obtained.

The alcohol solvent is methanol or ethanol, and when the alcohol solvent is ethanol, in step A and step B, the volume ratio of the toluene to ethanol is: toluene:ethanol=1:3～3.5, step C, the toluene and ethanol The volume ratio is greater than 1:3.5; when the alcohol solvent is methanol, in steps A and B, the volume ratio of the toluene to methanol is: toluene:methanol=1:1.0～1.1, step C, the volume ratio of the toluene to methanol The volume ratio is greater than 1:1.1.

The organic dye is one or more of solvent blue 70, solvent blue 05, solvent yellow 167, solvent red 119 or solvent red 122.

In step B, the amount of the expandable polystyrene particles added is such that the organic dye solution immerses the expandable polystyrene particles to a height of 2 cm.

Compared with prior art, the beneficial effect of the present invention is:

The method for preparing colored expandable polystyrene particles from expandable polystyrene particles provided by the invention is to add polystyrene particles into a mixed solvent containing organic dyes to swell the polystyrene particles, and the organic dyes enter The polystyrene particles swell in space, and the mixed solvent volatilizes to obtain colored polystyrene particles. In this method, the mixed solvent can be recycled and reused, has no pollution to the environment, and can effectively solve the problems of monochromatic polystyrene, dye inhibition effect during suspension polymerization of colored polystyrene, and internal coloring unevenness during direct dyeing. The invention uses few kinds of reagents for preparing colored polystyrene particles, simple process, uniform dyeing inside the polystyrene particles, and low preparation cost.

Detailed ways

The following examples only exemplify the preparation methods of polystyrene particles with two colors. The actual preparation is not limited to the following two types. Two or more dyes can be added according to the principle of color ratio to prepare polystyrene particles of desired color.

Example 1

In a 1-liter reactor, a stirring paddle is installed at the middle port, a condenser is installed at one side port, and condensed water is introduced. Add 120ml of toluene, 370ml of absolute ethanol and 4g of blue organic dye Solvent Blue 70 from the other side port and stir for 30min at a stirring speed of 150r/min; then, add 100g of expandable polystyrene particles and stir for 90min at a stirring speed of 150r/min, and prepare the liquid level gauge number, when the liquid level of the solution is lower than the liquid level gauge number, add toluene solvent to the liquid level gauge number; add 70ml of absolute ethanol after 2h and continue stirring for 10min, filter and dry to get blue Expandable polystyrene particles.

Example 2

Measure 150ml of toluene, 160ml of methanol and 2g of solvent red 122, a bright red organic dye, into a 1-liter reaction kettle, install a stirring paddle in the middle port, install a condenser in one side port, and feed condensed water, stir for 30 minutes, and the stirring speed is 120r/min; then, add 90g expandable polystyrene particles, stir for 90min, the stirring speed is 120r/min, and make a liquid level gauge number, when the solution level is lower than the liquid level gauge number, add toluene solvent to Liquid level gauge; after 2 hours, add 90ml of methanol and continue to stir for 10 minutes, filter and dry to obtain bright red expandable polystyrene particles.

Claims (4)

1. A method for preparing colored expandable polystyrene particles by expandable polystyrene particles, is characterized in that, specifically comprises the following steps: A. At room temperature, add toluene, alcohol solvent and 1 to 10 g of organic dyes to a three-necked flask connected with a condenser tube and a mechanical stirrer in sequence, and stir for 10 to 30 minutes at a stirring speed of 100 to 180 r/min to obtain Contains organic dye solutions; B. Add 80 to 100 g of expandable polystyrene particles to the solution containing organic dyes obtained in step A, and at a stirring speed of 100 to 180 r/min, the stirring time is 60 to 120 min, and a liquid level gauge is prepared. When the liquid level of the solution is lower than the liquid level gauge number, add toluene solvent to the liquid level gauge number; C. After 1-2 hours, add the same alcohol solvent as in step A and continue stirring for 10-20 minutes. After filtering and drying, colored expandable polystyrene particles are obtained. 2. a kind of method for preparing colored expandable polystyrene particles by expandable polystyrene particles according to claim 1, is characterized in that: described alcohol solvent is methyl alcohol or ethanol, and when alcohol solvent is ethanol, In step A and step B, the volume ratio of the toluene to ethanol is: toluene:ethanol=1:3～3.5, step C, the volume ratio of the toluene to ethanol is greater than 1:3.5; when the alcohol solvent is methanol, the step In step A and B, the volume ratio of toluene to methanol is: toluene:methanol=1:1.0-1.1, and in step C, the volume ratio of toluene to methanol is greater than 1:1.1. 3. a kind of method for preparing colored expandable polystyrene particles by expandable polystyrene particles according to claim 1, is characterized in that: described organic dyestuff is solvent blue 70, solvent blue 05, solvent One or more of Yellow 167, Solvent Red 119 or Solvent Red 122. 4. A method for preparing colored expandable polystyrene particles by expandable polystyrene particles according to claim 2, characterized in that: in step B, the amount of expandable polystyrene particles is organic It is enough that the dye solution is immersed in the expandable polystyrene particles and the height is 2cm.