Method for preparing a composite construction material

Patent metadata

Field	Value
Publication number	US-2025033249-A1
Application number	US-202418782175-A
Country	US
Kind code	A1
Filing date	Jul 24, 2024
Priority date	Jul 25, 2023
Publication date	Jan 30, 2025
Grant date	—

Abstract

A method for preparing a composite construction material, the method including: combining plastic waste and construction waste, such as construction debris, crushed rock, stone, concrete rubbles, soil, or a mixture thereof, thereby forming a waste mixture; and curing the waste mixture under oxygen-free conditions thereby melting or softening at least a portion of the plastic waste and forming the composite construction material.

First claim

What is claimed is:

1 . A method for preparing a composite construction material, the method comprising:
combining plastic waste and construction waste thereby forming a waste mixture; and curing the waste mixture under oxygen-free conditions thereby melting or softening at least a portion of the plastic waste and forming the composite construction material.

2 . The method of claim 1 , wherein the construction waste comprises concrete, bitumen, asphalt, rubble, rock, aggregate, construction debris, crushed rock, stone, concrete rubble, soil, crushed glass, brick, tile, ceramic, gypsum board, or a mixture thereof.

3 . The method of claim 1 , wherein the plastic waste comprises polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, polystyrene, acrylonitrile butadiene styrene, polycarbonate, nylon, poly(methyl methacrylate), polylactic acid (polylactide), polyether sulfone, polyoxymethylene, polyether ether ketone, polyetherimide, polyphenylene oxide, polyphenylene sulphide, polyvinylidene fluoride, polytetrafluoroethylene, or a mixture thereof.

4 . The method of claim 1 , wherein the plastic waste comprises polyethylene, polypropylene, or a mixture thereof.

5 . The method of claim 1 , wherein the composite construction material comprises at least 5% by weight of the plastic waste relative to the total weight of plastic waste and construction waste.

6 . The method of claim 1 , wherein the composite construction material comprises at least 10% by weight of the plastic waste relative to the total weight of plastic waste and construction waste.

7 . The method of claim 1 , wherein the step of combining plastic waste and construction waste further comprises combining water thereby forming the waste mixture with a gravimetric water content of 5-20%; and moulding the waste mixture prior to curing the waste mixture.

8 . The method of claim 1 , wherein curing the waste mixture is conducted at a temperature at ±20° C. of a melting point of the plastic waste.

9 . The method of claim 1 , wherein curing the waste mixture is conducted at a temperature at ±5° C. of a melting point of the plastic waste.

10 . The method of claim 1 further comprising the step of determining the melting point of the plastic waste.

11 . The method of claim 1 , wherein the oxygen-free conditions comprise vacuum or an inert atmosphere comprising nitrogen, carbon dioxide, helium, argon, or a mixture thereof.

12 . The method of claim 1 , wherein the composite construction material has an unconfined compressive strength of at least 2.4 MPa measured in accordance with ASTM D2166M-16.

13 . The method of claim 1 , wherein the construction waste comprises construction debris, crushed rock, stone, concrete rubbles, soil, or a mixture thereof; the plastic waste comprises polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, polystyrene, or a mixture thereof; the composite construction material comprises at least 5-40% by weight of the plastic waste relative to the total weight of plastic waste and construction waste; curing the waste mixture is conducted at a temperature at ±20° C. of a melting point of the plastic waste; and wherein the oxygen-free conditions comprise vacuum or an inert atmosphere comprising nitrogen, carbon dioxide, helium, argon, or a mixture thereof.

14 . The method of claim 13 , wherein the composite construction material has an unconfined compressive strength of at least 2.4 MPa measured in accordance with ASTM D2166M-16.

15 . The method of claim 1 , wherein the construction waste comprises construction debris, crushed rock, stone, concrete rubbles, soil, or a mixture thereof; the plastic waste comprises polyethylene, polypropylene, or a mixture thereof; the composite construction material comprises at least 10-40% by weight of the plastic waste relative to the total weight of plastic waste and construction waste curing the waste mixture is conducted at a temperature at ±5° C. of a melting point of the plastic waste; and wherein the oxygen-free conditions comprise vacuum or an inert atmosphere comprising nitrogen, carbon dioxide, helium, argon, or a mixture thereof.

16 . The method of claim 14 , wherein the composite construction material has an unconfined compressive strength of 2.4-7 MPa measured in accordance with ASTM D2166M-16.

17 . The method of claim 15 further comprising the step of determining the melting point of the plastic waste.

18 . The method of claim 1 further comprising applying a surface treatment to at least one surface of the composite construction material, wherein the surface treatment comprises a radiative cooling coating, a radiative cooling paint, or a mixture thereof.

19 . The method of claim 18 , wherein the radiative cooling coating comprises silicone and a metal oxide selected from the group consisting of magnesium oxide, aluminium oxide, titanium oxide and silicon oxide.

20 . The method of claim 18 , wherein the radiative cooling paint comprises titanium dioxide, barium sulphate, and a polyvinylidene fluoride-hexafluoropropylene copolymer.

Assignees

• Univ Hong Kong Science & Tech

Inventors

• Ng Charles Wang Wai
• So Pui San
• Lau Sze Yu

Classifications

• C04B2201/50

  for the mechanical strength · CPC title

• C04B41/61

  Coating or impregnation · CPC title

• C04B41/5041

  Titanium oxide or titanates · CPC title

• C04B41/65

  with inorganic materials · CPC title

• C04B26/045 Primary

  Polyalkenes · CPC title