SU513055A1 - The method of obtaining granulated aminoplast - Google Patents

Description

one

The invention relates to the production of plastics, it is intended for the production of granulated aminoplastic, widely used for the manufacture of products for technical and domestic purposes. . A method is known for producing a granulated aminoplast by mixing the powders of the aminoplast with a liquid component, which is a 1.5% aqueous solution of urea. The process is carried out by pre-cold mixing and hot displacement of the components at a temperature of 70-110 ° C, followed by sieving the raw granulate, jcyniKOH and sieving the dry granulate

The disadvantage of the known method: granulated aminoplast is the complexity of the technological process, due to the presence of additional blending operations, preliminary screening of the raw granulate and drying, as well as the fact that the granulate has insufficient processability in processing. The latter has a loose structure, low crushiness (flowability over a funnel for about 20 seconds and). This leads to a decrease in the accuracy of the dosage during pressing, to a lesser degree of precision measurement of the finished products.

The purpose of the invention is to simplify the process, as well as to improve the sealing properties of ammonia gas. The goal is achieved by melting naphthalene as a liquid component. At the same time, naphthalene is introduced into a mixture of 5.5–2 wt. hours per 100 weight. am aminoplast.

Fine naphthalene is introduced into the dry weight of the aminoplast, which can be carried out by the grinding stage of the latter. The mixture is then stirred by heating at a temperature of 80-lOO f. by screwing or rolling. With JTOM, the crystalline naphthalene melts, wetting the powder particles, compacting it and the method ;; ivu agglomeration. The resulting material is ground and dispersed into fractions. The main fraction of the granulate has a particle size of 0.25-2 mm. The obtained granulated amino amylum ceramide is used in articles made of standard samples and tested using conventional methods and the well-known technology used in the processing of urea press materials.

Granular aminoplast, H: (roro j tnnbiM in the indicated method, for all the flow of i and opi-ch

jei requirements GSHGT 9359-69, has improved pressing properties: high fluidity, good flowability, improved dosage accuracy during compression. Compared with granulated aminoplast using a urea solution, the strength of the urea increases in strength. 1.5-2 times, the weight of tablets decreases by more than 2 times. The technological process will be implemented by eliminating additional operations, especially drying, j

Example 1. Microdisperse naphthalene, 2 wt., Is introduced one hour before the end of grinding into the powdered amineglast located in a ball mill. hours {per 100 weight.h. aminoplast) and stirred for 1 hour, then the mixture is sieved and fed into the hopper of the screw machine with an adhesion screw. Mixing is carried out at the following temperature conditions (in ° C): I zone (loading) 40-50, Q zone 80-90, W zone (unloading) 80-100. In the D and W zones, naphthalene melts, wets and softens the particles of the aminoplast, facilitating their agglomeration. Due to intensive mixing and heat treatment, spherical granules are formed, which move to the discharge opening. The granulate is then subjected to seeding. The coarse fraction is crushed and mixed with the main, which has a grain size of 0.25-2 mm. The fine fraction is returned to the auger. The granulate obtained has improved pressing properties.

Example 2. To the powdered aminoplast, 1 weight.h is added to the end of the grinding stage. (per 100 parts by weight of aminoplast) of liquid naphthalene and crushed in a ball mill for 40 minutes. Then the mixture is sifted out from mechanical impurities and subjected to rolling at a temperature of the working roll 80-90 and an idle roll 30-35 ° C for 40-50 sec. -You this naphthalene, melts, wets and softens the press powder, contributing to the formation of a dense flat sheet. The rolled mass is crushed, sifted out from particles less than 0.25 mm in size. The fines fraction is formed up to 10% and is processed by adding during milling. The granulate has improved pressing properties.

Example 3. In a ball mill for 30 minutes before discharging the crushed amino to 0.5 weight.h. (per 100 weight.h. aminoplast) powdered naphthalene. The mixture after sieving is subjected to milling at a temperature of the work roll 85-90 and idle 30-35 ° C for 30-40 seconds. In the following, the process is carried out as described in Example 2.

The granular aminoplast obtained according to examples 1-E is processed into products by direct pressing, injection molding, and injection molding.

Finished products have a good appearance, increased accuracy of size and weight. The main indicators of granulated aminoplast are given in the table.

Bulk weight, g / cm

Strength at static bending, kgf / cm

The specific impact on iron, kgf. cm / cm

Heat resistance according to Martens, ° С

Shrinkage,%

Funnel flowability, s

Standard cup hardening time, s

Flowability, mm

Specific volumetric resistance, ohm cm

0.6-0.7

0.650.6

0.75

810873 665 831

7.4 119 0.7 And

and / b

/ b

65 160 70 70

154

160

1.6. 1D1-12 3.10

1.6., 6.

5130ft

OO

Claims (2)

The invention formula for the ulu sheshi flowability of the resulting granulate, in ). The method of producing granulated amnoflorable naphthalene, the formation by blending poro-amino acids with a liquid component at a temperature j 2. The method according to claim 1, characterized in that 70-1 OO-S, followed by grinding, and sifting that naphthalene is taken in an amount of 0.5-2 parts by weight on VA (Shem, characterized in that, for the purpose of 100 parts by weight of the amioshista. as a liquid component you will take off