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CN-122011669-A - Method for adding polyoxymethylene tracer and application of tracer

CN122011669ACN 122011669 ACN122011669 ACN 122011669ACN-122011669-A

Abstract

The invention belongs to an adding method and application of a polyoxymethylene tracer, wherein the adding method comprises the steps of dividing raw material polyoxymethylene into at least two parts, uniformly mixing the tracer with one part of raw material polyoxymethylene to prepare master batch, fully mixing the master batch with other raw material polyoxymethylene or a composition of the other raw material polyoxymethylene and an additive, and feeding the fully mixed materials into a double-screw extruder for mixing and granulating, wherein the tracer is metal oxide or salt which cannot be disabled due to reaction or temperature change in the production process of the polyoxymethylene, the mass ratio of the mixture of the polyoxymethylene and the additive to the tracer is 100:0.003-0.01, and the tracer has the advantages of being low in content, meeting identification sensitivity, having no influence on the performance of matrix resin, having no influence on the application environment of the material, being high in operability, being convenient for quick identification and high in accuracy.

Inventors

  • HE YAMIN
  • ZHANG HAITAO
  • Mao Xuran
  • XU CHUAN
  • ZHANG MENGKANG
  • GU CHAOHUI
  • LIU WEI

Assignees

  • 河南心连心化学工业集团股份有限公司

Dates

Publication Date
20260512
Application Date
20251222

Claims (10)

  1. 1. A method for adding a polyoxymethylene tracer is characterized by comprising the steps of dividing raw material polyoxymethylene into at least two parts, uniformly mixing the tracer with one part of raw material polyoxymethylene to prepare a master batch, fully mixing the master batch with other raw material polyoxymethylene or a composition of the other raw material polyoxymethylene and an additive, and mixing and granulating the fully mixed materials in a double-screw extruder; the tracer is metal oxide or salt which can not fail due to reaction or temperature change in the production process of the polyoxymethylene; The mass ratio of the mixture of the polyoxymethylene and the additive to the tracer is 100:0.003-0.01.
  2. 2. A method of adding a polyoxymethylene tracer according to claim 1, wherein said tracer is an oxide or salt of scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium.
  3. 3. The method of claim 1, wherein the additive comprises a lubricant, a formaldehyde absorbent, a primary antioxidant and a secondary antioxidant.
  4. 4. A method for adding a polyoxymethylene tracer according to claim 3, wherein the lubricant is one or a mixture of pentaerythritol ester stearic acid, polyethylene wax, silicone powder, ethylene bis stearamide or stearate, the formaldehyde absorbent is melamine, methylolmelamine or melamine-formaldehyde condensate, the main antioxidant is diethylene glycol ether-bis (3-tert-butyl-4-hydroxy-5-methylphenyl) acrylic acid or tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester, and the auxiliary antioxidant is one or a mixture of three [2, 4-di-tert-butylphenyl ] phosphite and bis 26-di-tert-butyl-4-methylphenyl pentaerythritol diphosphate.
  5. 5. The method for adding a polyoxymethylene tracer according to claim 3, wherein said method comprises the steps of: step 1, taking a tracer and part of polyformaldehyde, and putting the mixture into a double-cone mixer to mix to prepare a master batch, wherein the mass ratio of the part of polyformaldehyde to the tracer is 10-20:0.003-0.01; step 2, subdividing the rest polyformaldehyde in the step 1 into two parts, and putting one part of polyformaldehyde and additives into the master batch in the step 1 for uniform mixing to prepare a premix; Step 3, placing the other part of polyformaldehyde in the step 2 into the premix for uniform mixing to prepare a mixture; step 4, enabling the mixture in the step 3 to enter a double-screw extruder through a weightless feeding machine for granulation; and 5, putting the particles in the step 4 into a drying box for drying, and obtaining the polyoxymethylene containing the tracer.
  6. 6. The method for adding a polyoxymethylene tracer according to claim 5, wherein the stirring speed of the master batch prepared in the step 1 is 500-1000 rpm, and the stirring time is 30-60 min; The stirring speed of the premix prepared in the step 2 is 500-1000 rpm, and the stirring time is 20-40 min; And (3) preparing the mixture in the step (3), wherein the stirring speed is 500-1000 rpm, and the stirring time is 15-30 min.
  7. 7. The method of claim 5, wherein the mass ratio of the polyoxymethylene in the step 2 to the polyoxymethylene in the step 3 is 3:4.
  8. 8. The method for adding the polyoxymethylene tracer according to claim 5, wherein the control temperature of each zone of the twin-screw extruder in the step 4 is 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃ and 190 ℃ respectively, the temperature of a machine head is 185 ℃, the main feeding amount is 200-500 kg/h, the screw rotating speed is 200-500 r/min, and the vacuum degree is-0.1 to-0.5 MPa.
  9. 9. The method for adding a polyoxymethylene tracer according to claim 5, wherein the drying temperature of the drying oven in step 5 is 80-120 ℃ and the drying time is 2-4 hours.
  10. 10. Use of a tracer according to any of claims 1-9 in polyoxymethylene.

Description

Method for adding polyoxymethylene tracer and application of tracer Technical Field The invention belongs to the technical field of polyoxymethylene production, and particularly relates to a polyoxymethylene tracer addition method and application of a tracer. Background Polyoxymethylene (POM), also known as polyacetal, acetal resin, foreign name polymorphide, is known as "supersteel" or "siren steel", and the molecule is a high density, high crystallinity linear polymer without side chains. The POM is an engineering plastic with excellent performance, and is called steel-capturing and super-steel in foreign countries. POM has metal-like hardness, strength and rigidity, has good self-lubricity, good fatigue resistance, and high elasticity over a wide temperature and humidity range, and in addition, it has good chemical resistance. POM is replacing some of the markets traditionally occupied by metals, such as replacing zinc, brass, aluminum and steel, with lower costs than many other engineering plastics, and has been widely used in the fields of electronics, machinery, meters, light industry, automobiles, building materials, agriculture, etc., since the advent of the POM. However, in the serious homogenization of many polyoxymethylene manufacturers and brands in the market, products produced by different manufacturers under the same process are difficult to identify and distinguish, and the situation of secondary filling occurs, so that the market is disturbed and the brand construction is influenced. In order to solve the technical problems, some enterprises adopt a mode of adding fluorescent agents to mark for identification, anti-counterfeiting and identification, but the addition of fluorescent substances can cause the performance of materials to be reduced, and the precipitation and leakage of fluorescent markers can be harmful to the environment and organisms, and further, some enterprises select a mode of adding magnesium oxide for marking, but the effect of marking cannot be achieved when the adding amount is too small, and the strength of the polyoxymethylene can be improved and the marking effect can be achieved when the adding amount is too large, but the defects of product discoloration and toughness reduction can occur at the same time, namely, the appearance and the performance of the polyoxymethylene can be changed. Based on the above reasons, how to provide a method for marking polyoxymethylene without changing the appearance and performance of polyoxymethylene becomes a technical problem to be solved by enterprises. Disclosure of Invention In order to make up for the defects, the invention provides a method for adding a polyoxymethylene tracer and application of the tracer, so as to solve the technical problems in the prior art. The technical scheme adopted for solving the technical problems is as follows: A method for adding a polyoxymethylene tracer comprises the steps of dividing raw material polyoxymethylene into at least two parts, uniformly mixing the tracer with one part of raw material polyoxymethylene to prepare a master batch, fully mixing the master batch with other raw material polyoxymethylene or a composition of the other raw material polyoxymethylene and an additive, and feeding the fully mixed materials into a double-screw extruder for mixing and granulating, wherein the tracer is metal oxide or salt which cannot be disabled due to reaction or temperature change in the production process of the polyoxymethylene, and the mass ratio of the mixture of the polyoxymethylene and the additive to the tracer is 100:0.003-0.01. Preferably, the tracer is an oxide or salt of scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, or lutetium. Preferably, the additives include a lubricant, a formaldehyde absorber, a primary antioxidant, and a secondary antioxidant. Preferably, the lubricant is one or a mixture of pentaerythritol ester stearic acid, polyethylene wax, silicone powder, ethylene bis-stearamide or stearate, the formaldehyde absorbent is melamine, methylolmelamine or melamine-formaldehyde condensate, the main antioxidant is diethylene glycol ether-bis (3-tert-butyl-4-hydroxy-5-methylphenyl) acrylic acid or tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester, and the auxiliary antioxidant is one or a mixture of three [2, 4-di-tert-butylphenyl ] phosphite and bis 26-di-tert-butyl-4-methylphenyl pentaerythritol diphosphate. The invention also provides an adding method of the polyoxymethylene tracer, which comprises the following steps: step 1, taking a tracer and part of polyformaldehyde, and putting the mixture into a double-cone mixer to mix to prepare a master batch, wherein the mass ratio of the part of polyformaldehyde to the tracer is 10-20:0.003-0.01; step 2, subdividing the rest polyformaldehyde in the step 1 into two parts, and