Polymeric Material with a Multimodal Pore Size Distribution

Patent metadata

Field	Value
Publication number	US-2016102185-A1
Application number	US-201414895108-A
Country	US
Kind code	A1
Filing date	Jun 6, 2014
Priority date	Jun 12, 2013
Publication date	Apr 14, 2016
Grant date	—

Abstract

A polymeric material having a multimodal pore size distribution is provided. The material is formed by applying a stress to a thermoplastic composition that contains first and second inclusion additives dispersed within a continuous phase that includes a matrix polymer. Through the use of particular types of inclusion additives and careful control over the manner in which such additives are dispersed within the polymer matrix, the present inventors have discovered that a unique, multimodal porous structure can be achieved.

First claim

1 - 31 . (canceled)

32 . A porous polymeric material that contains a thermoplastic composition, the thermoplastic composition including a continuous phase in which a first inclusion additive and second inclusion additive are dispersed in the form of discrete first and second domains, respectively, the continuous phase including a matrix polymer, wherein a plurality of micropores are formed at and/or around the first domains that have an average cross-sectional dimension of from about 0.5 to about 30 micrometers, and wherein a plurality of nanopores are formed at and/or around the second domains that have an average cross-sectional dimension of from about 50 to about 500 nanometers.

33 . The porous polymeric material of claim 32 , wherein the micropores have an average cross-sectional dimension of from about 60 to about 450 nanometers.

34 . The porous polymeric material of claim 32 , wherein the nanopores have an average cross-sectional dimension of from about 1 to about 20 micrometers.

35 . The porous polymeric material of claim 32 , wherein the first domains have an average cross-sectional dimension of from about 0.05 to about 50 micrometers.

36 . The porous polymeric material of claim 32 , wherein the second domains have an average cross-sectional dimension of from about 50 to about 500 nanometers.

37 . The porous polymeric material of claim 32 , wherein the porous network further comprises a plurality of second nanopores that are formed at and/or around the second domains.

38 . The porous polymeric material of claim 32 , wherein the second nanopores have an average cross-sectional dimension of from about 1 to about 50 nanometers.

39 . The porous polymeric material of claim 32 , wherein the total pore volume of the polymeric material is from about 15% to about 80%.

40 . The porous polymeric material of claim 32 , wherein the polymeric material has a density of about 1.2 grams g/cm 3 or less.

41 . The porous polymeric material of claim 32 , wherein the continuous phase constitutes from about 60 wt. % to about 99 wt. % of the thermoplastic composition, the first inclusion additive constitutes from about 1 wt. % to about 30 wt. % of the composition based on the weight of the continuous phase, and the second inclusion additive constitutes from about 0.05 wt. % to about 20 wt. % of the composition based on the weight of the continuous phase.

42 . The porous polymeric material of claim 32 , wherein the matrix polymer includes a polyester or polyolefin.

43 . The porous polymeric material of claim 32 , wherein the matrix polymer has a glass transition temperature of about 0° C. or more.

44 . The porous polymeric material of claim 32 , wherein the first inclusion additive is a polyolefin.

45 . The porous polymeric material of claim 32 , wherein the second inclusion additive is a polyepoxide.

46 . The porous polymeric material of claim 32 , wherein the thermoplastic composition further contains a third inclusion additive that is dispersed within the continuous phase in the form of discrete third domains.

47 . The porous polymeric material of claim 46 , wherein the third domains have an average cross-sectional dimension of from about 1 to about 50 nanometers.

48 . The porous polymeric material of claim 46 , wherein the network further comprises a plurality of nanopores formed at and/or around the third domains that have an average cross-sectional dimension of from about 1 to about 50 nanometers.

49 . The porous polymeric material of claim 46 , wherein the third inclusion additive includes a nanoclay.

50 . The porous polymeric material of claim 46 , wherein the third inclusion additive constitutes from about 0.05 wt. % to about 20 wt. %, based on the weight of the continuous phase.

51 . The porous polymeric material of claim 32 , wherein the thermoplastic composition further comprises an interphase modifier.

52 . The porous polymeric material of claim 32 , wherein the micropores are elongated and the nanopores are generally spherical.

53 . The porous polymeric material of claim 32 , wherein the porous network is distributed in a substantially homogeneous fashion throughout the material.

54 . The porous polymeric material of claim 32 , wherein the micropores and/or nanopores are distributed in generally parallel columns.

55 . A method for forming the porous polymeric material of claim 32 , the method comprising drawing the thermoplastic composition while in a solid state to form the porous network.

56 . The method of claim 55 , wherein the composition is drawn at a temperature of from about −50° C. to about 50° C.

57 . The method of claim 55 , wherein the composition is drawn at a temperature that is at least about 10° C. below the glass transition temperature of the matrix polymer and/or the first inclusion additive.

58 . The method of claim 55 , wherein the composition is mechanically drawn.

Assignees

• Kimberly Clark Co

Inventors

• Topolkaraev Vasily A
• Mceneany Ryan J
• Tower Theodore T
• Biggs David Glen
• Scholl Neil T
• Eby Thomas A
• Carrillo Antonio J

Classifications

• C08J5/18

  Manufacture of films or sheets · CPC title

• C08J2323/12

  Polypropene · CPC title

• C08J2367/04

  Polyesters derived from hydroxy carboxylic acids, e.g. lactones (C08J2367/06 takes precedence) · CPC title

• C08J2423/08

  Copolymers of ethene (C08J2423/16 takes precedence) · CPC title

• C08J9/0061 Primary

  characterized by the use of several polymeric components · CPC title