Modified flexible polypropylene insulating material and preparation method and use thereof

Patent metadata

Field	Value
Publication number	US-2024352241-A1
Application number	US-202218294627-A
Country	US
Kind code	A1
Filing date	Aug 3, 2022
Priority date	Aug 4, 2021
Publication date	Oct 24, 2024
Grant date	—

Abstract

The invention belongs to the field of insulating materials, in particular cable insulating materials, and particularly relates to a modified flexible polypropylene insulating material, and preparation method and use thereof. The modified flexible polypropylene insulating material comprises a propylene-based continuous phase, and a rubber phase and a grafted phase derived from an unsaturated bond-containing polymerizable monomer dispersed in the propylene-based continuous phase; wherein, the modified flexible polypropylene insulating material has a content of xylene solubles of 10-55 wt %, preferably 15-45 wt %, more preferably 18-40 wt %, and still more preferably 20-40 wt %, based on the total weight of the modified flexible polypropylene insulating material; the content of structural units derived from the unsaturated bond-containing polymerizable monomer and in a grafted state in the modified flexible polypropylene insulating material is 0.3-6 wt %, and preferably 0.7-5 wt %; the flexural modulus of the modified flexible polypropylene insulating material is 200-1000 MPa, preferably 200-950 MPa, more preferably 200-700 MPa, and still more preferably 250-600 MPa; preferably, the ratio of the mass of the structural units derived from the unsaturated bond-containing polymerizable monomer in xylene insolubles to the mass of the structural units derived from the unsaturated bond-containing polymerizable monomer in the modified flexible polypropylene insulating material is more than 0.1, preferably 0.3-0.9. The modified flexible polypropylene insulating material of the invention can give consideration to both mechanical property and electrical property at a higher working temperature, and is suitable for working conditions of high temperature and high operating field strength.

First claim

1 . A modified flexible polypropylene insulating material comprising a propylene-based continuous phase, and a rubber phase and a grafted phase derived from an unsaturated bond-containing polymerizable monomer dispersed in the propylene-based continuous phase; wherein, the modified flexible polypropylene insulating material has a content of xylene solubles ranging from 10 wt % to 55 wt %, preferably from 15 wt % to 45 wt %, more preferably from 18 wt % to 40 wt %, and still more preferably from 20 wt % to 40 wt %, based on the total weight of the modified flexible polypropylene insulating material; the content of structural units derived from the unsaturated bond-containing polymerizable monomer and in a grafted state in the modified flexible polypropylene insulating material ranges from 0.3 wt % to 6 wt %, and preferably from 0.7 wt % to 5 wt %; the flexural modulus of the modified flexible polypropylene insulating material ranges from 200 MPa to 1000 MPa, preferably from 200 MPa to 950 MPa, more preferably from 200 MPa to 700 MPa, and still more preferably from 250 MPa to 600 MPa; preferably, the ratio of the mass of the structural units derived from the unsaturated bond-containing polymerizable monomer in xylene insolubles to the mass of the structural units derived from the unsaturated bond-containing polymerizable monomer in the modified flexible polypropylene insulating material is more than 0.1, preferably from 0.3 to 0.9.

2 . The modified flexible polypropylene insulating material according to claim 1 , wherein the unsaturated bond-containing polymerizable monomer is an alkenyl-containing functional monomer; the content of structural units derived from the alkenyl-containing functional monomer and in a grafted state in the modified flexible polypropylene insulating material ranges from 0.4 wt % to 6 wt %, and preferably from 1 wt % to 5 wt %; the D50 of the grafted phase is less than 300 nm, preferably from 10 nm to 250 nm, and more preferably from 50 nm to 200 nm.

3 . The modified flexible polypropylene insulating material according to claim 1 , wherein the unsaturated bond-containing polymerizable monomer is an anhydride monomer and an alkenyl-containing functional monomer; the content of structural units derived from the anhydride monomer and the alkenyl-containing functional monomer and in a grafted state in the modified flexible polypropylene insulating material ranges from 0.3 wt % to 5 wt %, preferably from 0.7 wt % to 3 wt, and the content of structural units derived from the anhydride monomer and in a grafted state ranges from 0.05 wt % to 2 wt %, preferably from 0.2 wt % to 0.5 wt %; the D50 of the grafted phase is less than 170 nm, preferably from 10 nm to 150 nm, and more preferably from 55 nm to 110 nm.

4 . The modified flexible polypropylene insulating material according to claim 1 , wherein the modified flexible polypropylene insulating material has at least one of the following characteristics: the melt flow rate under the load of 2.16 kg at 230° C. ranges from 0.5 g/10 min to 15 g/10 min, preferably from 0.6 g/10 min to 10 g/10 min, and further preferably 0.8 g/10 min to 6 g/10 min; the elongation at break is greater than or equal to 200%, and preferably greater than or equal to 300%; the tensile strength is more than 5 MPa, preferably from 10 MPa to 25 MPa.

5 . The modified flexible polypropylene insulating material according to claim 1 , wherein the modified flexible polypropylene insulating material has at least one of the following characteristics:
the maximum working temperature of the modified flexible polypropylene insulating material is greater than or equal to 90° C., preferably from 100° C. to 160° C., and more preferably from 110° C. to 140° C.; the breakdown field strength E 9 at 110° C. of the modified flexible polypropylene insulating material is greater than or equal to 285 kV/mm, preferably from 290 kV/mm to 800 kV/mm, and more preferably from 300 kV/mm to 750 kV/mm; the direct current volume resistivity ρ vg at 110° C. and 40 kV/mm field strength of the modified flexible polypropylene insulating material is greater than or equal to 1.0×10 13 Ω·m, preferably from 1.5×10 13 Ω·m to 1.0×10 20 Ω·m; the dielectric constant at 110° C. and 50 Hz of the modified flexible polypropylene insulating material is greater than 2.0, and preferably ranging from 2.1 to 2.5.

6 . The modified flexible polypropylene insulating material according to claim 3 , wherein the anhydride monomer is selected from anhydrides having at least one olefinic unsaturation; preferably, the anhydride monomer is selected from maleic anhydride and itaconic anhydride; further preferably, the anhydride monomer is maleic anhydride.

7 . The modified flexible polypropylene insulating material according to claim 2 , wherein the alkenyl-containing functional monomer is selected from at least one of monomers having a structure represented by formula 1,

wherein R b , R c , R d are each independently selected from H and substituted or unsubstituted alkyl; R a is selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted ester group, substituted or unsubstituted carboxyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclyl, cyano, and substituted or unsubstituted silyl.

8 . The modified flexible polypropylene insulating material according to claim 7 , wherein R b , R c , R d are each independently selected from H and substituted or unsubstituted C 1 -C 6 alkyl; preferably R b , R c , R d are each independently selected from H and substituted or unsubstituted C 1 -C 3 alkyl; R a is selected from substituted or unsubstituted C 1 -C 20 alkyl, substituted or unsubstituted C 1 -C 20 alkoxy, substituted or unsubstituted C 6 -C 20 aryl, substituted or unsubstituted C 1 -C 20 ester group, substituted or unsubstituted C 1 -C 20 carboxyl, substituted or unsubstituted C 3 -C 20 cycloalkyl, substituted or unsubstituted C 3 -C 20 heterocyclyl, cyano, and substituted or unsubstituted C 3 -C 20 silyl; the substituent group is selected from halogen, hydroxy, amino, C 1 -C 12 alkyl, C 3 -C 6 cycloalkyl, C 1 -C 12 alkoxy, and C 1 -C 12 acyloxy; preferably, R a is selected from substituted or unsubstituted C 1 -C 12 alkyl, substituted or unsubstituted C 1 -C 18 alkoxy, substituted or unsubstituted C 6 -C 12 aryl, substituted or unsubstituted C 1 -C 12 ester group, substituted or unsubstituted C 1 -C 12 carboxyl, substituted or unsubstituted C 3 -C 12 cycloalkyl or heterocyclyl, and cyano; preferably, the substituent group is selected from halogen, C 1 -C 6 alkyl, and C 3 -C 6 cycloalkyl; more preferably, R a is selected from substituted or unsubstituted C 1 -C 6 alkyl, substituted or unsubstituted C 1 -C 12 alkoxy, substituted or unsubstituted C 6 -C 8 aryl, substituted or unsubstituted C 1 -C 6 ester group, substituted or unsubstituted C 1 -C 6 carboxyl, substituted or unsubstituted C 3 -C 6 cycloalkyl, substituted or unsubstituted C 3 -C 6 heterocyclyl, and cyano.

9 . The modified flexible polypropylene insulating material according to claim 8 , wherein R b , R c , R d are each independently selected from H and substituted or unsubstituted C 1 -C 6 alkyl;
R a is selected from a group of formula 2, a group of formula 3, a group of formula 4, a group of formula 5, a group of formula 6, a group that is a combination of a group of formula 6 and a group of formula 7, and a heterocyclic group;

wherein R 4 -R 8

Assignees

• China Petroleum & Chem Corp
• Beijing Res Inst Chemical Ind China Petroleum & Chemical Corp
• Univ Tsinghua

Inventors

• Shao Qing
• He Jinliang
• Yuan Hao
• Li Qi
• Zhang Yaru
• Hu Jun
• Wang Mingdi
• Huang Shangshi
• Li Juan
• Hu Shixun
• Zhang Qi
• Gao Dali
• Shi Hongwei

Classifications

• C08F255/02 Primary

  on to polymers of olefins having two or three carbon atoms · CPC title

• C08F255/04

  on to ethylene-propylene copolymers {(C08F255/023 takes precedence)} · CPC title

• H01B3/441

  from alkenes · CPC title

• C08L2312/00

  Crosslinking · CPC title

• C08L2205/22

  Mixtures comprising a continuous polymer matrix in which are dispersed crosslinked particles of another polymer · CPC title