Weatherability and durability of low-density polyethylene nanocomposites with clay, silica and zinc oxide

Patent metadata

Field	Value
Publication number	US-2015191582-A1
Application number	US-201414151349-A
Country	US
Kind code	A1
Filing date	Jan 9, 2014
Priority date	Jan 9, 2014
Publication date	Jul 9, 2015
Grant date	—

Abstract

A low-density polyethylene nanocomposite comprising 5 weight percent or more of at least one nanoscale filler selected from the group consisting of montmorillonite clay, silica and zinc oxide. Changes in weatherability of the three low-density polyethylene nanocomposites based on the nanoscale fillers are determined. A surface area of the nanoscale filler in the nanocomposites is from 10 m 2 /g to 50 m 2 /g.

First claim

1 : A low-density polyethylene nanocomposite comprising 5 weight percent or more of at least one nanoscale filler selected from the group consisting of montmorillonite clay, silica and zinc oxide.

2 : The nanocomposite of claim 1 , comprising nanoscale montmorillonite clay modified with a quaternary ammonium salt.

3 : The nanocomposite of claim 1 , comprising nanoscale silica.

4 : The nanocomposite of claim 1 , comprising zinc oxide.

5 : The nanocomposite of claim 1 , wherein a surface area of the nanoscale filler is from 10 m 2 /g to 50 m 2 /g.

6 : The nanocomposite of claim 2 ,
wherein a surface area of the montmorillonite clay is about 10.9 m2/g, an agglomerate size of the clay is about 8 μm, the clay is composed of individual platelets having a thickness of about 1 nm and an aspect ratio of greater than 50, and an interlayer spacing, determined by XRD, is about 2.52 nm.

7 : The nanocomposite of claim 2 , wherein the clay is modified with N,N-dimethyl dehydrogenated tallow quaternary ammonium chloride at a concentration of about 95 mequiv/100 g clay.

8 : The nanocomposite of claim 3 , wherein the nanosilica has an average primary particle size of about 40 nm and a BET surface area of about 50 m 2 /g.

9 : The nanocomposite of claim 4 , wherein the zinc oxide is a free flowing powder with a density of about 5.6 g/cm 3 , an average particle size of about 30 nm, and a specific surface area of about 35 m 2 /g.

10 : A method of preparing the low-density polyethylene nanocomposite of claim 1 , comprising:
melt mixing the nanoscale filler with the low-density polyethylene in an extruder; maintaining a melt temperature in the range of 190 to 205° C.; pelletizing a compounded resin comprising 5 weight % or more of the nanofiller; and drying to obtain the low-density polyethylene nanocomposite.

11 : The method of claim 10 , further comprising injection molding at a nozzle temperature of about 215° C. and an injection pressure of 5000 psi.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Siddiqui Mohammad N
• Redhwi Halim H
• Hussain Syed

Classifications

• C08K3/22

  of metals · CPC title

• C08K5/544 Primary

  containing nitrogen · CPC title

• B29C45/0001

  characterised by the choice of material · CPC title

• B29K2023/0633

  LDPE, i.e. low density polyethylene · CPC title

• C08K3/36

  Silica · CPC title