Wet laid paper and paperboard products with high wet strength and method of making the same
A method of making paper and paperboard products, including absorbent structures, where the method includes mixing ultra-high molecular weight (“UHMW”) glyoxalated polyvinylamide (“GPVM”) adducts and high molecular weight (“HMW”) anionic polyacrylamide (“APAM”) with the furnish during stock preparation of a wet laid papermaking process.
1 . A paper or paperboard product, comprising:
lignocellulosic and/or cellulosic fibers;
ultra-high molecular weight glyoxalated polyvinylamide (UHMW GPVM) adducts and high molecular weight anionic polyacrylamide (HMW APAM) complex, the UHMW GPVM adducts and HMW APAM complex being present in the paper or paperboard product by an amount of at least 0.05% by weight;
a dichloropropanol concentration of less than 50 ppb;
a chloropropanediol concentration of less than 300 ppb; from 0 to 0.09% by weight polyaminoamide-epihalohydrin; and
a wet tensile strength of at least 10% of the value of a dry tensile strength of the product,
wherein the UHMW GPVM adducts and HMW APAM complex comprises: (i) HMW APAM having a weight average molecular weight (Mw) of from greater than 500,000 to 2,000,000 daltons; (ii) UHMW GPVM having a weight average molecular weight (Mw) of from greater than 2,000,000 to about 50,000,000 daltons; or (iii) both (i) and (ii).
2 . The paper or paperboard product of claim 1 , wherein: (i) the product comprises from 0.25 to 1.5% by weight of the UHMW GPVM adducts and HMW APAM complex; (ii) the wet tensile strength of the product is at least 15% of the value of the dry tensile strength of the product; or (iii) both (i) and (ii).
3 . The paper or paperboard product of claim 1 , wherein: (i) the product is free from the polyaminoamide-epihalohydrin as measured using an “Adipate test”; (ii) the wet tensile strength of the product is at least 20% of the value of the dry tensile strength of the product; or (iii) both (i) and (ii).
4 . A paper or paperboard product comprising:
from 80 to 99% by weight lignocellulosic and/or cellulosic fibers;
ultra-high molecular weight glyoxalated polyvinylamide (UHMW GPVM) adducts and high molecular weight anionic polyacrylamide (HMW APAM) complex, the UHMW GPVM adducts and HMW APAM complex being present in the paper or paperboard product by an amount of 0.05 to 1.5% by weight; and
from 0 to 0.5% by weight polyvinylamine,
wherein the UHMW GPVM adducts and HMW APAM complex comprises: (i) HMW APAM having a weight average molecular weight (Mw) of from greater than 500,000 to 2,000,000 daltons; (ii) UHMW GPVM adducts having a weight average molecular weight (Mw) of from greater than 2,000,000 to about 50,000,000 daltons; or (iii) both (i) and (ii).
5 . The paper or paperboard product of claim 4 , wherein: (i) the product comprises from 0.25 to 1.5% by weight of the UHMW GPVM adducts and HMW APAM complex; (ii) the wet tensile strength of the product is at least 15% of the value of the dry tensile strength of the product; or (iii) both (i) and (ii).
6 . The paper or paperboard product of claim 4 , wherein the UHMW GPVM adducts and HMW APAM complex comprises: (i) HMW APAM having a weight average molecular weight (Mw) of from 550,000 to 1,500,000 daltons; (ii) UHMW GPVM adducts having a weight average molecular weight (Mw) of from 8,000,000 to about 25,000,000 daltons; or (iii) both (i) and (ii).
7 . The paper or paperboard product of claim 4 , wherein the UHMW GPVM adducts and HMW APAM complex comprises HMW APAM having an acrylic acid to acrylamide molar ratio of from 7:93 to 40:60.
8 . The paper or paperboard product of claim 4 , wherein the UHMW GPVM adducts and HMW APAM complex comprises HMW APAM having an acrylic acid to acrylamide molar ratio of from 12:88 to 35:65.
9 . The paper or paperboard product of claim 8 , wherein the product comprises from 0.25 to 1.5% by weight of the UHMW GPVM adducts and HMW APAM complex.
10 . The paper or paperboard product of claim 4 , wherein the product exhibits a repulping time at least 20% less than a similar PAE resin-treated paper or paperboard product having a comparable defibering level and a substantially equal wet strength measured when fully wetted after a 2 hour aqueous soak.
11 . The paper or paperboard product of claim 10 , wherein the product exhibits the repulping time of at least 20% less than the similar PAE resin-treated paper or paperboard product during repulping in water at a pH equal to or greater than about 9.
12 . The paper or paperboard product of claim 4 , wherein the product comprises from 0.01 to 0.5% by weight of the polyvinylamine.
13 . A method of making a paper or paperboard product, comprising:
forming an aqueous stock mixture comprising from 80 to 99% by weight solids lignocellulosic and/or cellulosic fibers, ultra-high molecular weight glyoxalated polyvinylamide (UHMW GPVM) adducts and high molecular weight anionic polyacrylamide (HMW APAM) complex, the UHMW GPVM adducts and HMW APAM complex being present in the stock mixture by an amount of 0.05 to 1.5% by weight solids, from 0 to 0.09% by weight solids of a polyaminoamide-epihalohydrin, and from 0 to 0.5% by weight solids of a polyvinylamine; and
sheeting and drying the aqueous stock mixture, thereby giving the product,
wherein the UHMW GPVM adducts and HMW APAM complex comprises: (i) HMW APAM having a weight average molecular weight (Mw) of from greater than 500,000 to 2,000,000 daltons; (ii) UHMW GPVM adducts having a weight average molecular weight (Mw) of from 8,000,000 to about 25,000,000 daltons; or (iii) both (i) and (ii).
14 . The method of claim 13 , wherein the aqueous stock mixture is formed without addition of the polyaminoamide-epihalohydrin, and wherein the product is free from the polyaminoamide-epihalohydrin as measured using an “Adipate test”.
15 . The method of claim 13 , wherein the UHMW GPVM adducts and HMW APAM complex comprises HMW APAM having an acrylic acid to acrylamide molar ratio of from 7:93 to 40:60.
16 . The method of claim 13 , wherein the aqueous stock mixture is formed with 0.01 to 0.5% by weight solids of the polyvinylamine.
17 . The method of claim 13 , wherein the paper or paperboard product comprises: (i) a dichloropropanol concentration of less than 50 ppb and a chloropropanediol concentration of less than 300 ppb; a wet tensile strength at least 15% of the value of the dry tensile strength of the paper or paperboard product; or (iii) both (i) and (ii).