Polyvinyl acetal-based resin composition

Patent metadata

Field	Value
Publication number	US-9512310-B2
Application number	US-201314431324-A
Country	US
Kind code	B2
Filing date	Sep 20, 2013
Priority date	Sep 28, 2012
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

The present invention provides a polyvinyl acetal resin composition exerting excellent mechanical strength over a wide temperature range from low temperatures to high temperatures. The present invention provides a polyvinyl acetal resin composition containing a polyvinyl acetal resin and a resin having a crosslinked structure, the polyvinyl acetal resin composition having a structure in which the resin having a crosslinked structure is dispersed as a dispersed phase in the polyvinyl acetal resin as a continuous phase, the polyvinyl acetal resin composition having a maximum value of a loss tangent derived from the polyvinyl acetal resin at 40° C. or higher and a maximum value of a loss tangent derived from the resin having a crosslinked structure at 10° C. or lower in measurement of a dynamic viscoelasticity spectrum at a frequency of 10 Hz.

First claim

The invention claimed is:

1. A polyvinyl acetal resin composition containing a polyvinyl acetal resin and a resin having a crosslinked structure,
the polyvinyl acetal resin composition having a structure in which the resin having a crosslinked structure is dispersed as a dispersed phase in the polyvinyl acetal resin as a continuous phase,
the polyvinyl acetal resin composition having a maximum value of a loss tangent derived from the polyvinyl acetal resin at 40° C. or higher and a maximum value of a loss tangent derived from the resin having a crosslinked structure at 10° C. or lower in measurement of a dynamic viscoelasticity spectrum at a frequency of 10 Hz, and
the polyvinyl acetal resin composition comprising a graft copolymer of the polyvinyl acetal resin and the resin having a crosslinked structure, wherein the graft copolymer has a grafting ratio of 2 to 150% by weight.

2. The polyvinyl acetal resin composition according to claim 1 ,
wherein, in measurement of the dynamic viscoelasticity spectrum at a frequency of 10 Hz, a tensile storage elastic modulus is 1×10 7 to 3×10 9 Pa·s in a range covering 80% or more of a temperature range from a temperature at which the loss tangent derived from the polyvinyl acetal resin reaches the maximum value to a temperature at which the loss tangent derived from the resin having a crosslinked structure reaches the maximum value.

3. The polyvinyl acetal resin composition according to claim 1 ,
wherein the amount of the polyvinyl acetal resin is 30 to 95% by weight and the amount of the resin having a crosslinked structure is 5 to 70% by weight in 100% by weight of the total of the polyvinyl acetal resin and the resin having a crosslinked structure.

4. The polyvinyl acetal resin composition according to claim 1 ,
wherein the dispersed phase comprising the resin having a crosslinked structure has an average dispersion size of 0.1 to 10 μm.

5. The polyvinyl acetal resin composition according to claim 1 ,
wherein the resin having a crosslinked structure has a gel fraction of 10 to 98% by weight.

6. The polyvinyl acetal resin composition according to claim 1 , being free of a plasticizer.

7. The polyvinyl acetal resin composition according to claim 1 ,
wherein the resin having a crosslinked structure is a (meth)acrylic resin having a crosslinked structure.

8. The polyvinyl acetal resin composition according to claim 7 , obtained by polymerization of a monomer constituting the (meth)acrylic resin in the presence of the polyvinyl acetal resin.

Assignees

• Sekisui Chemical Co Ltd

Inventors

• Nagai Yasuharu
• MIKAYAMA Kaoru

Classifications

• C08L33/14 Primary

  of esters containing halogen, nitrogen, sulfur, or oxygen atoms in addition to the carboxy oxygen · CPC title

• C08L29/14

  Homopolymers or copolymers of acetals or ketals obtained by polymerisation of unsaturated acetals or ketals or by after-treatment of polymers of unsaturated alcohols · CPC title

• C08L2205/22

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

• C08F261/12

  on to polymers of unsaturated acetals or ketals · CPC title

• C08L33/06

  of esters containing only carbon, hydrogen and oxygen, which oxygen atoms are present only as part of the carboxyl radical · CPC title