CN105504742A - Method for preparing novel enhanced polycarbonate material by using waste/used compact discs and printed circuit boards - Google Patents

Abstract

The invention relates to the recycling of non-metallic particles produced by discarded CDs and broken printed circuit boards, and belongs to the technical field of waste recycling. The present invention is based on two kinds of waste materials: polycarbonate material obtained from waste optical discs and non-metallic particles obtained from printed circuit boards, the particle size of non-metallic particles is controlled to be 50-200 mesh, and the addition ratio is 10%-15%. The blending of waste materials resulted in a novel non-metallic particle-reinforced polycarbonate material. Because the mechanical strength of the polycarbonate material obtained from the recycling of waste optical disks is greatly reduced, it does not meet the application strength requirements of polycarbonate materials. However, the present invention not only realizes the recycling of two kinds of waste materials, but also obtains a mechanical strength that meets the requirements of polycarbonate materials. Carbonate materials use standard new non-metallic particle reinforced polycarbonate materials.

Description

Method for preparing new reinforced polycarbonate material from waste discs and printed circuit boards

technical field

The invention relates to the recovery and utilization of non-metallic particles produced by waste CDs and broken printed circuit boards, and belongs to the technical field of waste recycling and synthesis of new materials.

Background technique

With the rapid development of the optical disc industry, the output and consumption of optical discs are still increasing, which directly leads to the accumulation of waste optical discs year by year. The optical disc is a composite product composed of multi-layer component materials. Functional layers such as recording, reflection, and printing primary protection are attached to the disc base in sequence, but the properties of each functional layer vary greatly, and the manufacturing materials of different types of optical discs are also different. . Optical discs are divided into non-rewritable optical discs according to their functions, such as CD-ROM, DVD-ROM and rewritable optical discs, such as CD-RW, DVD-RAM, and rewritable optical discs CD-R. As far as CD is concerned, its basic structure consists of three layers of polycarbonate (PC) substrate, aluminum reflective layer and ultraviolet curing glue (UV). At least 93% of the material composition is polycarbonate, and it also contains a small amount of zinc , silicon, gold and silver and other useful elements.

At present, there are physical methods and chemical methods for recycling waste discs. The physical method is mainly a mechanical crushing method, which directly applies a mechanical device to rub the optical disc to remove the surface layer and the reflective layer from the optical disc. This method has a wide range of options, and the raw materials do not need to be classified, and can be fully automated. The disadvantage is that the loss rate is high, and the metal in the reflective layer cannot be recovered. The chemical method is to use a stripping agent such as alkali or acid to react with the metal of the reflective layer, so that the product can be dissolved into the solution, and at the same time, the protective adhesive layer and the printing layer are peeled off. This method has low loss rate, recyclable metal, and low direct cost, but It may cause secondary pollution of the stripper. The physical method and chemical method will finally get the disc-based polycarbonate PC material, and the treatment of PC is mainly divided into incineration method, landfill method and melting regeneration method. Although the incineration method has the advantages of large processing capacity and high efficiency, it will produce a large amount of harmful gases after incineration, including carcinogens, causing harm to the atmosphere and the environment, and the equipment investment and maintenance costs are high. However, polycarbonate is a high molecular polymer, which is difficult to degrade in the environment, and landfilling is not a reasonable disposal method. Melt regeneration is to crush, dry, extrude and granulate polycarbonate for melt regeneration to produce new PC products.

As an integral part of electronic products, printed circuit boards are usually made of glass fiber-reinforced phenolic resin or epoxy resin, on which various components are welded, which contain a large number of recyclable metal and non-metal components, with high Resource recovery value. At present, the recycling technologies for waste printed circuit boards mainly include three categories:

Heat treatment, including incineration, pyrolysis, direct smelting, etc., is a relatively simple method, and has certain advantages in volume reduction, treatment scale and efficiency, but it causes serious environmental pollution. The chemical treatment method mainly uses acid, ionic liquid, etc. to treat the circuit board, but this method cannot deal with the circuit board with complex structural components, and the leachate and residue are generally corrosive or toxic, which is easy to cause secondary pollution. The mechanical physical treatment method is currently the most important method for recycling waste circuit boards in China. The metal material is separated. The non-metallic powder components are mainly glass fiber and thermosetting epoxy resin. The method has the advantages of simple process, low economic cost and little impact on the environment.

Contents of the invention

In view of the characteristics of the large amount of non-metallic particles obtained from waste optical discs and broken waste printed circuit boards, which are difficult to handle, and the mechanical strength of the recycled waste optical disc polycarbonate disc base is greatly reduced and cannot be reused, resulting in a waste of resources. The polycarbonate disk base obtained from the processing of the optical disc is melt-mixed and granulated with non-metallic particles to obtain a new type of non-metallic particle-reinforced polycarbonate material, thereby realizing the recycling of two kinds of waste materials.

A method for preparing a novel reinforced polycarbonate material from non-metallic particles produced by crushing waste CDs and waste printed circuit boards, characterized in that it has the following process and steps:

a) Soak the waste optical discs in 1mol/L sodium hydroxide solution, and obtain a pure polycarbonate disc base after treatment for 4 hours, wash, crush, and dry;

b) Mix the non-metallic particles obtained by crushing and sorting waste circuit boards with a silane coupling agent at a solid-to-liquid ratio of 100:1 and stir at high speed for 20 minutes to modify them, and screen out particles with different particle sizes of 50-200 mesh after drying;

c) After the modified non-metallic particles of different particle sizes are mixed with the broken polycarbonate particles in a mass ratio of 10% to 15% by a high-speed mixer, they are melted and extruded by a twin-screw extruder at high temperature to granulate, and then A new reinforced polycarbonate material was produced using an injection molding machine.

The method of the invention mixes recycled polycarbonate obtained from waste optical discs and non-metallic particles obtained from discarded circuit boards under certain conditions to obtain a reinforcing material, which solves the problem of disposal of waste CDs and non-metallic particles, and realizes two Recycling of waste. In addition, the non-metallic particles of waste circuit boards are added to recycled polycarbonate as a reinforcing agent, so that its mechanical strength and dimensional stability have been significantly improved, and it has become a high-potential new material.

detailed description

Embodiments of the present invention will now be described below.

Example 1

Soak waste optical discs in 1mol/L sodium hydroxide solution for 4 hours to obtain polycarbonate disc bases, which are cleaned, dried and crushed. Mix the broken non-metallic particles of the circuit board with the silane coupling agent at a solid-to-liquid ratio of 100:1 and stir at high speed for 20 minutes to modify them, and dry them for later use. Mix the broken non-metallic particles of the circuit board with the silane coupling agent at a solid-to-liquid ratio of 100:1 and stir at high speed for 20 minutes to modify them, and dry them for later use. Take a sufficient amount of prepared broken polycarbonate particles and add non-metallic particles with a particle size of 50 mesh modified broken circuit boards in a mass ratio of 100:12. After mixing evenly, extrude and granulate with a twin-screw extruder. The standard test model is obtained, and the tensile strength of the recycled reinforced material is 35MPa, the bending strength is 78MPa, and the heat distortion temperature is 148°C.

Example 2

Soak waste optical discs in 1mol/L sodium hydroxide solution for 4 hours to obtain polycarbonate disc bases, which are cleaned, dried and crushed. Mix the broken non-metallic particles of the circuit board with the silane coupling agent at a solid-to-liquid ratio of 100:1 and stir at high speed for 20 minutes to modify them, and dry them for later use. Take a sufficient amount of prepared broken polycarbonate particles and add non-metallic particles with a particle size of 160 meshes in a mass ratio of 100:12. After mixing evenly, extrude and granulate with a twin-screw extruder, and use an injection molding machine The standard test model is obtained, and the tensile strength of the recycled reinforced material is 55MPa, the bending strength is 80MPa, and the heat distortion temperature is 150°C.

Claims (1)

1. A method for preparing novel reinforced polycarbonate material with the non-metallic particles produced by the crushing of waste CDs and waste printed circuit boards, is characterized in that it has the following process and steps: a) Soak the waste optical discs in 1mol/L sodium hydroxide solution, and obtain a pure polycarbonate disc base after treatment for 4 hours, wash, crush, and dry; b) Mix the non-metallic particles obtained by crushing and sorting waste circuit boards with a silane coupling agent at a solid-to-liquid ratio of 100:1 and stir at high speed for 20 minutes to modify them, and screen out particles with different particle sizes of 50-200 mesh after drying; c) After the modified non-metallic particles of different particle sizes are mixed with the broken polycarbonate particles in a mass ratio of 10% to 15% by a high-speed mixer, they are melted and extruded by a twin-screw extruder at high temperature to granulate, and then A new reinforced polycarbonate material was produced using an injection molding machine.