Laminated articles for microbial removal and low pressure drop filtration, methods of making, and methods of using same

1. A laminated article comprising:

a) a porous fibrous nonwoven matrix;

b) a plurality of guanidine-functionalized metal silicate particles enmeshed within the porous fibrous nonwoven matrix, the guanidine-functionalized metal silicate particles comprising:

a metal silicate particle that is modified with at least one silane having the formula

X 3-n R a n Si—Y-G,

wherein:

n is 0, 1, or 2;

each R a , if present, is independently an alkyl, aralkyl, or aryl;

Y is a divalent group comprising an alkylene having 2 to 20 carbons;

G is a guanidine group of the formula —NH—C(═NH)—NH 2 ; and

each X is independently alkoxy or acyloxy;

c) a first substrate; and

d) a second substrate sealed to the first substrate along at least a portion of a perimeter of the first substrate, wherein the porous fibrous nonwoven matrix is disposed between the first substrate and the second substrate.

2. The laminated article of claim 1 , wherein the first substrate and the second substrate are independently selected from a spunbond polypropylene, a spunbond polyamide, a spunbond blend of polyamide and polyester, a spunbond polyethylene, a spunbond polyester, a spunbond polybutylene terephthalate, and a spunbond polypropylene.

3. The laminated article of claim 1 , wherein the first substrate and the second substrate independently comprise a spunbond material comprising a gram per square meter basis weight (gsm) of 10 to 200 gsm, inclusive.

4. The laminated article of claim 1 , wherein the laminated article provides a turbidity of less than 0.2 nephelometric turbidity units (NTU) according to the Turbidity Test.

5. The laminated article of claim 1 , wherein the metal silicate particle is a magnesium silicate particle.

6. The laminated article of claim 1 , wherein each of the first substrate and the second substrate is liquid permeable.

7. A method of making a laminated article, the method comprising:

a) providing a plurality of fibers;

b) providing a plurality of guanidine-functionalized metal silicate particles;

c) mixing the plurality of guanidine-functionalized metal silicate particles and the plurality of fibers together to form a porous fibrous nonwoven matrix having the guanidine-functionalized metal silicate particles enmeshed within the porous fibrous nonwoven matrix;

d) providing a first substrate;

e) providing a second substrate;

f) disposing the porous fibrous nonwoven matrix having the guanidine-functionalized metal silicate particles between the first substrate and the second substrate; and

g) sealing the second substrate to the first substrate along at least a portion of a perimeter of the first substrate.

8. The method of claim 7 , wherein the providing a plurality of guanidine-functionalized metal silicate particles comprises:

i) reacting an O-methylisourea salt with a linker comprising the formula

X 3-n R a n Si—Y—NH 2 ,

wherein:

n is 0, 1, or 2;

each R a , if present, is independently an alkyl, aralkyl, or aryl;

Y is a divalent group comprising an alkylene having 2 to 20 carbons; and

each X is independently alkoxy or acyloxy;

to form a guanidine-functionalized linker; and

ii) forming a mixture of the guanidine-functionalized linker and metal silicate particles, such that the guanidine-functionalized linker reacts with hydroxyl groups of the metal silicate particles to form covalent bonds between the guanidine-functionalized linker and the metal silicate particles, thereby forming the guanidine-functionalized metal silicate particles.

9. The method of claim 7 , wherein the sealing is performed using ultrasonic sealing, heat sealing, adhesive sealing, stitching, or a combination thereof.

10. The method of claim 7 , further comprising mixing at least one polymeric binder together with the plurality of guanidine-functionalized metal silicate particles and the plurality of fibers.

11. A method of removing microorganisms from a fluid sample, the method comprising:

a) providing a laminated article, the laminated article comprising:

1) a porous fibrous nonwoven matrix;

2) a plurality of guanidine-functionalized metal silicate particles enmeshed within the porous fibrous nonwoven matrix, the guanidine-functionalized metal silicate particles comprising:

a metal silicate particle that is modified with at least one silane having the formula

X 3-n R a n Si—Y-G

wherein:

n is 0, 1, or 2;

each R a , if present, is independently an alkyl, aralkyl, or aryl;

Y is a divalent group comprising an alkylene having 2 to 20 carbons;

G is a guanidine group of the formula —NH—C(═NH)—NH 2 ; and

each X is independently alkoxy or acyloxy;

3) a first substrate; and

4) a second substrate sealed to the first substrate along at least a portion of a perimeter of the first substrate, wherein the porous fibrous nonwoven matrix is disposed between the first substrate and the second substrate;

b) providing a fluid sample containing at least one microorganism strain; and

c) contacting the fluid sample with the laminated article such that at least a portion of the at least one microorganism strain is removed from the fluid sample.

12. The method of claim 11 , wherein the contacting comprises passing the fluid sample at least once through the laminated article.

13. The method of claim 12 , wherein the contacting comprises passing the fluid sample through the laminated article at a pressure of 4.0 pounds per square inch (psi) (27.58 kilopascals (kPa)) or less.

14. The method of claim 11 , wherein the laminated article reduces the amount of microorganism in the fluid sample by at least a factor of 100.

15. A filtration device comprising:

a) a container having inlet and outlet ports for liquid passage; and

b) a laminated article contained within the container, the laminated article comprising:

1) a porous fibrous nonwoven matrix;

2) a plurality of guanidine-functionalized metal silicate particles enmeshed within the porous fibrous nonwoven matrix, the guanidine-functionalized metal silicate particles comprising:

a metal silicate particle that is modified with at least one silane having the formula

X 3-n R a n Si—Y-G

wherein:

n is 0, 1, or 2;

each R a , if present, is independently an alkyl, aralkyl, or aryl;

Y is a divalent group comprising an alkylene having 2 to 20 carbons;

G is a guanidine group of the formula —NH—C(═NH)—NH 2 ; and

each X is independently alkoxy or acyloxy;

3) a first substrate; and

4) a second substrate sealed to the first substrate along at least a portion of a perimeter of the first substrate, wherein the porous fibrous nonwoven matrix is disposed between the first substrate and the second substrate.