Modified liquid diene rubbers

Patent metadata

Field	Value
Publication number	US-11773190-B2
Application number	US-201816753261-A
Country	US
Kind code	B2
Filing date	Oct 2, 2018
Priority date	Oct 5, 2017
Publication date	Oct 3, 2023
Grant date	Oct 3, 2023

Abstract

A modified liquid diene rubber (A) has a functional group (a) derived from an acid anhydride, and satisfies all the requirements (I) to (III) below: (I) The functional group equivalent weight of the functional groups (a) is in the range of 400 to 3,500 g/eq. (II) The polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 5,000 to 20,000. (III) The melt viscosity at 38° C. is not less than 3 Pa·s and X (K) is not less than 6100 K wherein X is the slope of a linear line passing through two points in a graph in which the two points are values of melt viscosity η (Pa·s) at 38° C. and 60° C. measured with a Brookfield viscometer which are plotted as Ln[η/(Pa·s)] on ordinate versus 1/T (K −1 ) on abscissa (with the proviso that T is temperature (K)).

First claim

The invention claimed is:

1. A rubber composition, comprising:
a modified liquid diene rubber (A); and
a solid rubber (B),
wherein the modified liquid diene rubber (A) has a functional group (a) derived from an acid anhydride, and satisfies (I), (II), and (III) below:
(I) a functional group equivalent weight of the functional groups (a) is in a range of 400 to 3,500 g/eq,
(II) a polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in a range of 5,000 to 20,000, and
(III) a melt viscosity at 38° C. is not less than 3 Pa·s and X (K) is not less than 6100 K wherein X is a slope of a linear line passing through two points in a graph in which the two points are values of melt viscosity η(Pa·s) at 38° C. and 60° C. measured with a Brookfield viscometer which are plotted as Ln[η/(Pa·s)] on ordinate versus 1/T (K −1 ) on abscissa wherein T is a temperature (K), and
the modified liquid diene rubber (A) is a product of reaction of a liquid diene rubber modified with an unsaturated carboxylic acid anhydride, and a compound of chemical formula (2) or (3):
R a —OH  (2)

wherein R a is a hydrogen atom or an optionally substituted alkyl group,
R b 2 —NH  (3)

wherein R b at each occurrence is a hydrogen atom or an optionally substituted alkyl group and is optionally the same as or different from one another.

2. A sealing material, comprising:
the rubber composition of claim 1 .

3. A tire bead filler rubber composition, comprising:
the rubber composition of claim 1 .

4. The tire bead filler rubber composition of claim 3 , wherein the tire bead filler rubber composition comprises:
100 parts by mass of the solid rubber (B),
1 to 20 parts by mass of the modified liquid diene rubber (A),
5 to 40 parts by mass of a phenolic resin (C), and
0.5 to 2.0 parts by mass of a curing agent (D).

Assignees

• Kuraray Co

Inventors

• Motoda Satoshi
• Kaneko Shuhei
• NOZASA Yu
• Uehara Yosuke
• Kashioka Masahiro
• Ueno Yoshikazu

Classifications

• Y02T10/86

  Optimisation of rolling resistance, e.g. weight reduction · CPC title

• C08C19/34 Primary

  reacting with oxygen or oxygen-containing groups · CPC title

• B60C1/00

  Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition · CPC title

• C08L7/00

  Compositions of natural rubber · CPC title

• C08L15/00

  Compositions of rubber derivatives (C08L11/00, C08L13/00 take precedence) · CPC title