Application examples of recycling technology of th

Examples of application of recycling technology for packaging plastic bottles

bottles include cool drink bottles, mineral water bottles, liquid food bottles, cosmetic bottles, etc. the materials used include polyethylene (PE), polyvinyl chloride (PVC), polyethylene terephthalate (PET), etc. Usually, mineral water bottles are made of PVC or pet, carbonated beverage bottles are made of pet, cool beverage bottles, liquid food bottles are made of PVC, PE, detergent bottles, cosmetic bottles, milk bottles, and lactic acid bacteria drinks are mostly made of PE

all kinds of recycled bottles are generally sorted manually first, and then recycled according to different materials. At present, many technologies and equipment have been used for the recycling and regeneration of all kinds of bottles.

(1) PET bottles are widely used in Coca Cola, Pepsi, Sprite and other carbonated beverages. At present, most of them are composed of PET bottles and HDPE bottle bottoms. The bottle cap material h selects the appropriate gear DPE, The trademark is biaxially oriented polypropylene (BOPP) film, which is adhered to the bottle body with EVA adhesive. The recycling and reuse of polyester bottles are through regenerative granulation. Alcoholysis and other methods. No matter what method is adopted, the polyester bottle should be separated from other bottles first, and the polyester bottle body should also be separated from the bottom of the bottle

① separation: the mixed collecting bottle enters the crusher through the conveyor belt for crushing, and then passes through density separation

② we are back again! " Raw granulation: extruder can be used for regenerative granulation. The separated pet scrap is extruded and granulated into pellets by extruder. In order to avoid the physical viscosity reduction caused by water absorption during extrusion, it should be dried before extrusion. The uses of pet pellets are as follows:

a, remanufacture PET bottles. Recycled pellets can not be used in direct contact with food, but can be used in the middle layer of three-layer PET bottles, and then made into carbonated beverage bottles

b. spinning fiber, recycled PET material can be used to spin fiber, used as pillow, mattress, sleeping bag, felt, etc

c. glass fiber reinforced material. Recycled PET reinforced by glass fiber has good heat resistance and mechanical strength. It can be used to make auto parts, such as heat-resistant auto wheelhouse, and its thermal distortion temperature can reach 240 degrees. Variable modulus of elasticity 9500mpa, bending strength 214 MPa, impact strength 15kf/m2

d. blending modification: Recycled PET material can be blended with other polymers to produce various modified materials. For example, blending with PE can obtain PET Blends with improved impact properties. Pe:pet is (10~50): (90~50): if a small amount of polypropylene is added, the dimensional stability of the blends can be significantly improved. Due to the large difference in polarity between PE and pet, compatibility treatment is required during blending, and the compatibility is generally improved by grafting modification of polyolefin

③ alcoholysis, pet waste is alcoholized in the presence of alkaline catalyst, and then binary anhydride and other polycondensation are added to obtain products with an acid value greater than 12. After dilution, filtration, and adding an appropriate amount of catalyst, alkyd resin paint can be prepared. The formula is shown in the table below. The reaction temperature is 80~85 ℃, Reaction 4~5h

alcoholysis of pet waste to make coating formula

material addition/% material addition/%

Pet material 25 N-hydroxymethylacrylamide 2

triethylene glycol 23 non-ionic emulsifier 0.9

dibutyl phthalate 18 anionic emulsifier 1.1

ethylene acetate 24 persulfate initiator 1.4~1.6

a-methylstyrene 7 water 130

methacrylic acid 1

.Another example is in 220~2 At 50oc, pet waste is reacted with polyols and solvated to produce a three-dimensional insulating paint, which meets the requirements of gb6109. ③ other, PET bottles can also be used to make plasticizer: 2-ethylhexyl terephthalate (DOTP), whose plasticizing effect is similar to that of dioctyl phthalate (DOP), and is slightly better than DOP in electrical properties and low-temperature flexibility. Waste PET bottles can also be made into adhesives and unsaturated polyester in a similar way to waste PET film (2) recycling of PVC bottles. The recycling process of PVC is as follows

pvc bottle cleaning, sorting and crushing fine crushing recycled products

first clean the PVC bottle with steam and lye and remove the trademark, then divide it mechanically and manually, and then crush the sorted PVC bottle twice, and finally get the fineness of 500~1200 μ M powder recycled products, the purity can reach 99.98%

(3) the recovery of PE bottles, the PE used as bottle material is mainly HDPE, including dairy bottles, food bottles, cosmetic bottles, etc. after sorting, the cleaned HDPE recycling bottles can be crushed and selected for the following purposes:

① use the colored coke bottle base

② use it for CO extruding the middle core layer of pipes

③ fill talc powder or glass fiber to make flower tea cups or injection molded products

④ it is compounded with this fiber and used as artificial wood. Because wood fiber has poor compatibility with HDPE, it is necessary to add appropriate coupling agent or use activated wood fiber

⑤ make artificial gravel, crush HDPE bottles into fine pieces or granules, and then use lead screws to stick yarn, metal and other gravel on the surface, and then mix it with concrete or asphalt for civil construction materials