Polyacrylamide as a volatile rust inhibitor and desiccant, and its use and production method

Abstract

A volatile rust inhibitor composition is disclosed that inhibits corrosion of a metallic material and includes about 1% to about 100% by weight of polyacrylamide. The volatile rust inhibitor composition may include a second volatile rust inhibitor selected from the group consisting of ammonium salts, triazoles, nitrites, nitrates, amine carboxylates, amines, carboxylic acids, aldehydes, acid anhydrides, and any combination thereof. A method for inhibiting rust of a metallic material using the volatile rust inhibitor composition is also disclosed.

Description

[Technical field]

[0001] Field of Disclosure The present disclosure relates to a volatile corrosion inhibitor composition comprising polyacrylamide for inhibiting corrosion of metallic materials. The volatile corrosion inhibitor composition exhibits excellent corrosion inhibition effect on both ferrous and non-ferrous alloys typically used in the industry, such as aluminum, copper, zinc, nickel, tin, silver and their alloys. [Background technology]

[0002] Background of the disclosure Corrosion during the transportation, storage and use of metal members and components used in various industries can be a significant problem. Thus, temporary protection of these metals against corrosion is an important step in the manufacture and assembly of these metallic materials. One way to provide this protection is by treating the environment surrounding the metal material, rather than the direct treatment of the metal itself, which is fairly labor intensive to apply and remove. The two most important factors in the environment that contribute to corrosion are humidity and contamination. Desiccants can reduce the relative humidity within a package or other enclosed environment. Volatile corrosion inhibitors (VCIs) can protect metal surfaces in such a way that moisture is prevented from corroding the metal surface by evaporating chemicals into the environment and depositing them on the metal surface, protecting the metal's native oxide layer, creating a molecular level barrier on the metal surface, and protecting the metal surface from contaminants in the environment or on the surface that promote corrosion. VCI materials are widely used to produce temporary corrosion protection for the surfaces of metallic materials. Summary of the Invention [Problem to be solved by the invention]

[0003] There are a variety of known desiccants products, including clays, silica gels, molecular sieves, calcium chloride, and magnesium chloride, and VCI products are also known in the market, including ammonium salts, nitrites, amines, amine salts, aldehydes, acid anhydrides, carboxylic acids, and carboxylates. There are also a number of products sold as VCI desiccants to be used in the form of emitters, diffusers, or otherwise coated on or incorporated into substrates. These products combine one or more of the above desiccants with one or more of the above VCIs. [Means for solving the problem]

[0004] Summary of disclosure A volatile rust inhibitor composition is disclosed that contains crosslinked polyacrylamide (PAM), non-crosslinked (i.e., linear) polyacrylamide, or a combination of linear and crosslinked polyacrylamide. The volatile rust inhibitor composition can function as both a volatile rust inhibitor (VCI) and a desiccant. The volatile rust inhibitor composition can include about 1% to about 100% by weight of polyacrylamide, which can be optionally crosslinked or linear. The volatile rust inhibitor composition can include up to about 99% by weight, or up to about 90% by weight of a second volatile rust inhibitor. The second volatile rust inhibitor can be selected from the group consisting of: ammonium salts (e.g., ammonium benzoate), triazoles (e.g., benzotriazole), nitrites (e.g., nitrites such as sodium nitrite), nitrates (e.g., nitrates such as sodium nitrate), amine carboxylates, amines, carboxylic acids, aldehydes, acid anhydrides, and any combination thereof. The volatile rust inhibitor composition may be packaged in a polymer, natural fiber, or nonwoven material, paper, or in any flexible or rigid breathable container, or may otherwise be used in bulk form.

[0005] A method of using polyacrylamide to prevent metal corrosion is disclosed. A method of producing a volatile rust inhibitor containing PAM is also disclosed. A method of preventing rusting of metal materials is disclosed, comprising the steps of: providing a metal material, optionally in a sealed environment; and providing a volatile rust inhibitor composition, where the volatile rust inhibitor composition prevents corrosion of the metal material. When present, the sealed environment can be a small bag or sachet made of any breathable material, placed in a polymer film, a control cabinet, or in a container or device with limited gas permeability. Alternatively, the volatile rust inhibitor composition can be coated on paper, foam, or any porous substrate. The volatile rust inhibitor composition can be extruded into a single or multi-layer polymer film or any cross section, injection molded into a part, or added to a liquid to form a gel / semi-solid medium. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a photograph of a steel panel after 24 hours of exposure, showing the different rust-inhibiting effects of certain compositions. [Diagram 2] FIG. 2 is a graph showing the relative humidity (RH) within packages with different desiccants over the first 10 days of testing with the chamber set at 40° C. and 95% RH. [Diagram 3] FIG. 3 is a graph showing the RH in packages with different desiccants during days 11 and 12 in a chamber set at 50° C. and 93% RH. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Detailed Description of the Disclosure The present disclosure relates to a volatile corrosion inhibitor composition containing polyacrylamide (PAM) that has excellent corrosion inhibition effects on both iron and certain non-ferrous metals such as aluminum. Volatile corrosion inhibitors containing PAM are used to prevent corrosion of metal materials and can also function as desiccants to remove moisture from the environment and provide protection to other types of metals as well by reducing the relative humidity level. The rust inhibition effect can be achieved without direct contact between the metal and the PAM. The VCI generation of polyacrylamide can be on-demand, or alternatively referred to as "smart", in that the polyacrylamide is responsive to the environment and will generate more VCI and absorb more moisture when the temperature and humidity of the environment increases and corrosion is more likely.

[0008] PAM has the following formula: [ka] It is a polymer having the formula: The polymers can be synthesized as simple linear or cross-linked structures. Cross-linked polymers can absorb and retain large amounts of water because the amide groups form strong hydrogen bonds with water molecules. The weight average molecular weight M of the polyacrylamide used in accordance with the present disclosure is w is approximately 1.0x10 6 g / mol ~ approx. 50x10 6 g / mol, approximately 1.5x10 6 g / mol ~ approx. 30x10 6 g / mol, approximately 2.0x10 6 g / mol ~ approx. 25x10 6 g / mol, approximately 1.0x10 6 g / mol ~ approx. 1.0x10 7 g / mol, or approximately 8.0x10 6 g / mol ~ approx. 18x10 6 g / mol. The PAM may be a polyacrylamide homopolymer, a copolymer containing acrylamide, or a combination thereof. Acrylamide-containing copolymers, such as copolymers of acrylamide and acrylic acid, show similar results due to the presence of a structure similar to the PAM formula.

[0009] The volatile rust inhibitor composition may contain about 1% by mass to about 100% by mass, about 10% by mass to about 90% by mass, about 10% by mass to about 50% by mass, about 10% by mass to about 20% by mass, about 20% by mass to about 90% by mass, about 20% by mass to about 80% by mass, about 30% by mass to about 80% by mass, about 40% by mass to about 95% by mass, about 40% by mass to about 100% by mass, about 50% by mass to about 100% by mass, about 60% by mass to about 100% by mass, about 80% by mass to about 100% by mass, about 80% by mass to about 90% by mass, about 90% by mass to about 100% by mass, or about 100% by mass of polyacrylamide. The polyacrylamide may be linear. The polyacrylamide may be a crosslinked polyacrylamide, and may be a PAM homopolymer, copolymer, or combinations thereof.

[0010] Without being limited to one theory, it is believed that PAM acts as a VCI by decomposing and / or hydrolyzing, thereby releasing ammonia and / or other compounds that inhibit the corrosion of metal materials. The rate of hydrolysis depends on the temperature and humidity of the environment, and thus higher temperatures and humidity result in the production of greater amounts of VCI. More specifically, for example, PAM functions as a VCI by releasing vapors such as amine-based compounds. PAM reacts with water to release amino groups (-NH) from the polymer chain. 2 ), which forms an ammonium ion. The nitrogen on the amino group can be attracted to polar metal surfaces, and once this attraction occurs, the remainder of the molecule repels water from the metal surface, reducing corrosion. This also releases the OH radical, which helps preserve the oxide layer on the metal surface. - group (see U.S. Pat. No. 7,824,482 B2).

[0011] Higher temperature and humidity accelerate the corrosion of metals. When the volatile corrosion inhibitor composition disclosed herein is placed in a closed container with metal materials and contaminants, VCI generation is "on demand", which means that the PAM is responsive to the environment and more VCI is generated when the temperature and humidity of the environment increases. Therefore, the volatile corrosion inhibitor composition disclosed herein may be called a responsive or smart VCI.

[0012] Any chemical that will increase the hydrolysis rate of the PAM can increase the amount of VCI produced and therefore improve its volatile corrosion inhibitor (VCI) performance. For example, adding a non-volatile base (having a pH greater than about 8.0) can increase the amount of ammonia released by polyacrylamide, thereby improving its ability as a VCI.

[0013] The rust-inhibiting effect of PAM can be increased by adding a second volatile rust inhibitor to the volatile rust inhibitor composition. The second volatile rust inhibitor can be any volatile rust inhibitor known for use in the art. The second volatile rust inhibitor can be a carboxylic acid, a carboxylate, an ammonium salt, a nitrite, an amine, an amine salt, an aldehyde, an acid anhydride, a triazole, or any combination thereof. The second volatile rust inhibitor can be selected from: ammonium benzoate, benzotriazole, sodium nitrite, a nitrate, an amine carboxylate, an amine, and any combination thereof. When present, the volatile rust inhibitor composition can contain up to about 90% by weight of the second volatile rust inhibitor. The volatile rust inhibitor composition may contain about 0.01% by mass to about 90% by mass, about 0.1% by mass to about 90% by mass, about 0.1% by mass to about 50% by mass, about 0.1% by mass to about 30% by mass, about 0.1% by mass to about 10% by mass, about 1% by mass to about 10% by mass, about 1% by mass to about 30% by mass, about 1% by mass to about 20% by mass, or about 5% by mass to about 10% by mass of the second volatile rust inhibitor.

[0014] The volatile rust inhibitor composition may contain one or more additives. The additives may be selected from silicates, carbonates, or oxides of alkali and alkaline metals or minerals such as sand, talc, mica, vermiculite, or organic fillers such as starch, cellulose-based materials, or resins such as polyethylene. When present, the volatile rust inhibitor composition may contain up to about 50% by weight of the additive. The volatile rust inhibitor composition may contain about 0.01% to about 50% by weight, about 0.1% to about 40% by weight, about 0.1% to about 30% by weight, about 0.1% to about 10% by weight, about 0.1% to about 5% by weight, about 1% to about 20% by weight, about 1% to about 10% by weight, or about 1% to about 5% by weight of the additive.

[0015] The volatile rust inhibitor composition may contain about 60% by mass to about 90% by mass, or about 80% by mass to about 90% by mass of polyacrylamide, and about 1% by mass to about 40% by mass, or about 1% by mass to about 10% by mass of one or more second volatile rust inhibitors. The volatile rust inhibitor composition may contain about 90% by mass of polyacrylamide and about 1% by mass to about 4% by mass of one or more second volatile rust inhibitors. The volatile rust inhibitor composition may contain about 1% by mass to about 30% by mass, or about 10% by mass to about 20% by mass of polyacrylamide, and about 60% by mass to about 95% by mass, or about 70% by mass to about 90% by mass of one or more second volatile rust inhibitors. The volatile rust inhibitor composition may contain about 50% by mass to about 95% by mass of polyacrylamide, about 1% by mass to about 20% by mass of a second volatile rust inhibitor, and about 0.1% by mass to about 20% by mass of one or more additives. The volatile rust inhibitor composition may contain about 1% by mass to about 50% by mass of polyacrylamide, about 1% by mass to about 70% by mass of a second volatile rust inhibitor, and about 1% by mass to about 20% by mass of one or more additives.

[0016] In one embodiment, when a second volatile corrosion inhibitor is added to the volatile corrosion inhibitor composition, the PAM functions as both a desiccant and a volatile corrosion inhibitor, with the second volatile corrosion inhibitor functioning as an additional VCI. As a desiccant, the PAM absorbs moisture from the air and creates and maintains a lower humidity environment compared to a system without any desiccant.

[0017] For the volatile rust inhibitor composition of the present invention containing PAM and a second volatile rust inhibitor, the effectiveness of the volatile rust inhibitor composition is not substantially reduced. As used herein, a substantial reduction in effectiveness means that the effectiveness is reduced by more than about 10% with the addition of a second VCI. This was surprising because the combination of traditional desiccants, such as clay and silica gel, with known volatile rust inhibitors results in the desiccants absorbing a portion of the VCI, thereby reducing the effectiveness of the VCI, and at the same time reducing the effectiveness of the desiccant, which then has a lower ability to adsorb water, resulting in reduced VCI and desiccant capacity. It has been found that this is not the case with the combination of the volatile rust inhibitor composition of the present invention containing PAM and a second volatile rust inhibitor.

[0018] The volatile corrosion inhibitor composition is preferably applied to a high density spunbond polyethylene fiber (e.g., Tyvek (R) ), nonwoven materials, or polymeric films such as nylon, polyethylene, polyethylene terephthalate, or paper. Any known container used in the art with desiccants can be used to package the volatile rust inhibitor composition. It can also be packaged in any rigid container that allows gas and water vapor transmission. It may be sold and used in bulk form. The volatile rust inhibitor composition can be mixed, injection molded, extruded into a film, or added to a liquid to form a gel-like / semi-solid medium.

[0019] Metallic materials include those made of ferrous and non-ferrous metallic materials, such as copper and bronze. Furthermore, the use in combination with anti-rust components for non-ferrous metallic materials, such as copper and bronze, allows the demonstration of multiplicatively superior anti-rust capabilities for ferrous-based metallic materials as well as non-ferrous metallic materials.

[0020] The volatile rust inhibitor composition may include a chemical with a high pH that acts as a deliquescent material that can increase water adsorption of the package. The deliquescent material added to the volatile rust inhibitor composition may be, but is not limited to, calcium chloride, magnesium chloride, urea, sodium nitrate. The volatile rust inhibitor composition may further include an imidazole and / or triazole / azole compound to provide yellow metal protection. The volatile rust inhibitor composition may include about 1% to about 50%, about 5% to about 50%, or about 10% to about 30% by weight of a deliquescent material. The volatile rust inhibitor composition may include the deliquescent material calcium chloride. If present, the volatile rust inhibitor composition may include about 40% to about 80%, or about 50% by weight of polyacrylamide and about 5% to about 50% by weight of a deliquescent material, and optionally 1 to 40% of one or more second volatile rust inhibitors. The volatile rust inhibitor composition may contain about 40% by weight to about 80% by weight of polyacrylamide, about 10% by weight to about 30% by weight of one or more second volatile rust inhibitors, and about 10% by weight to about 30% by weight of a deliquescent material.

[0021] A method for preventing rusting of metal materials is disclosed. A method for protecting metals placed in a corrosive environment is also disclosed. The method includes providing a volatile corrosion inhibitor composition disclosed herein in the corrosive environment together with the metal. The PAM can act as a VCI by preventing or reducing corrosion of the metal, and can also act as a desiccant in some cases by removing moisture from the environment.

[0022] The duration of the rust-preventing effect of the composition is highly dependent on the humidity and temperature of the environment. It may also depend on the method of sealing the environment. If the composition is sealed in an aluminum foil bag with metal parts, it may continue to provide rust-preventing protection for several years, for example, about 2 years. If the composition is sealed in a polyethylene bag with metal parts, it may be too dependent on humidity and temperature, since the water vapor transmission rate of the packaging material is significantly different at different levels of temperature and humidity. Temperature and humidity also affect how much VCI is released by the PAM. Metal surface area may also make a difference in lifespan. Cast iron and fired metals with more surface area, or heavily contaminated metal surfaces, may reduce the duration of the rust-preventing effect of the composition, for example, to about 6 months to about 24 months, or about 6 months to about 12 months.

[0023] When sold in emitter pack form, the volatile rust inhibitor composition may be delivered by a packaging device capable of delivering a specific amount of the volatile rust inhibitor composition in a number of sachets made from a heat sealable material. It may also be delivered in any rigid container that allows water vapor transmission. When used in bulk, the volatile rust inhibitor composition may be placed in a container (aluminum foil bag or bucket or drum) and sealed and delivered to an enclosure, such as inside a metal enclosure.

[0024] The amount of the volatile rust inhibitor composition may be enclosed in any container known for use with traditional desiccants, such as a pouch or sachet, or in a polymer film, or coated on a paper, foam, or porous substrate. The sachet or pouch may be made from any breathable material, meaning that air passes through the material easily. The amount of the volatile rust inhibitor composition may be extruded into a monolayer or multilayer polymer film, injection molded into a part, or added to a liquid to form a gel or semi-solid medium. The amount of the volatile rust inhibitor composition (by weight) may be any amount known for use with traditional desiccants manufactured and sold in the market. For example, the amount may be from about 1 gram to about 1500 grams, from about 1 gram to about 700 grams, from about 1 gram to about 500 grams, from about 1 gram to about 100 grams, or from about 1 gram to about 50 grams. The size of the container depends on the volume of the space requiring rust protection. The pouch or sachet may then be placed in an environment, optionally a sealed environment, in the presence of a metal material. The sealed environment can be within a polymer film, a control cabinet, inside a device, or any container with limited gas permeability.

[0025] The volatile rust inhibitor composition may act by volatilizing and releasing amines and ammonia or otherwise providing a rust inhibitory effect, and optionally removing moisture from the environment. The volatile rust inhibitor composition may have a rust inhibitory effect for at least about 6 months, at least about 12 months, greater than about 2 years, or greater than about 3 years. The volatile rust inhibitor composition may have a rust inhibitory effect for about 6 months to about 3 years. EXAMPLES

[0026] Example 1 A test was conducted to investigate the rust-preventive effect on steel panels. Cold-rolled steel panels were heated to 90°C in an oven, and then immersed in a methanol solution containing 70 ppm Cl. - The panels were then placed into rectangular plastic holders and three of these holders were placed into 9X12 2 mil polyethylene bags. (R)Sachets (similar to ) were prepared with one of the following: i) 8 grams of 100% PAM, ii) 8 grams of PAM+VCI (a mixture of 90% PAM and 10% ammonium benzoate by weight), iii) 16 grams of clay, or iv) 16 grams of clay and ammonium benzoate in a 9 to 1 weight ratio (90% clay and 10% ammonium benzoate by weight). Controls, i.e. polyethylene bags without sachets, were also prepared. The packages were then placed in a chamber running the following IEC 60068-2-30 cycle: 6 hours at 25°C and about 98% relative humidity, 3 hours at 55°C and about 95% relative humidity, 9 hours at 55°C and about 93% relative humidity, and 6 hours at 25°C and 98% relative humidity. Figure 1 shows the panels upon inspection after 24 hours. Table 1 shows the percentage of corrosion observed on the panels upon inspection after 24 hours.

[0027] [Table 1]

[0028] The control panels (no PAM, no VCI, no desiccant) showed the highest level of corrosion. Panels stored in the presence of clay (a known traditional desiccant) along with VCI (ammonium benzoate) showed more corrosion than panels stored in the presence of clay alone. This is most likely due to adsorption of the VCI by the desiccant, thereby reducing the effectiveness of both the VCI and the desiccant.

[0029] PAM alone and PAM+VCI (ammonium benzoate) showed anti-rust effect and protected the panels from corrosion, with PAM+VCI (ammonium benzoate) providing the best protection.

[0030] Example 2 The desiccant effect of PAM was demonstrated by measuring the weight gain of the material, which indicates water adsorption. Weight gain tests were performed using 10 gram samples according to Mil-D-3464E test method. The weight of the samples was measured at 24 hour intervals. After steady state was reached, the humidity and temperature were adjusted to the following levels: Weight gain percentages are reported in the table below for PAM, PAM+VCI (10% ammonium benzoate), clay, and clay+VCI (10% ammonium benzoate by weight) samples at each temperature and humidity setting. Weight gain was not significantly affected by mixing VCI with PAM, as was the case when the same VCI mixture was added to clay.

[0031] [Table 2]

[0032] The delta values ​​between the weight gain of the PAM samples and the weight gain of the PAM / VCI samples, as well as the delta between the clay samples and the clay / VCI samples, were calculated from the data in Table 2 and are reported in Table 3, showing a greater change in the desiccant capacity of the clay in the presence of VCI compared to PAM in the presence of VCI.

[0033] [Table 3]

[0034] Example 3 Five 0.1 cubic meter frames were constructed from extruded aluminum rods. Each frame was placed inside a form-fitting polyethylene 4 mil bag, and three chloride-contaminated panels (prepared as in Example 2) were draped over the center of each frame before the bag was closed.

[0035] One 100 gram pack of either i) PAM, ii) calcium chloride superabsorbent polymer desiccant ("CaCl desiccant"), iii) clay, or iv) silica gel was placed at the bottom of each of the molded and filled polyethylene bags. One molded and filled polyethylene bag was placed as a control without any VCI or desiccant. The molded and filled polyethylene bags were sealed and then placed in a large environmental chamber set at 40° C. and 95% RH for 10 days, followed by 2 days at 50° C. and 93% RH.

[0036] Table 4 shows the average percentage of corrosion observed on the three panels after completion of this test. The results show the following order of corrosion protection levels: PAM > CaCl desiccant > silica gel, clay, and control.

[0037] [Table 4]

[0038] The packs were weighed before and after the test, and the percentage weight gain of the packs at the end of the test is shown in Table 5. The percentage weight gain shows the following order: CaCl desiccant > silica gel > PAM > clay. Although PAM showed less weight gain than silica gel and CaCl desiccant as far as water adsorption is concerned, PAM outperforms silica gel and CaCl desiccant in rust prevention.

[0039] [Table 5]

[0040] The humidity of each package was measured and recorded using an Onset MX2301A model data logger. Results for the first 10 days of testing with the chamber set at 40° C. and 95% RH are shown in Figure 2. Results for the final two days with the chamber set at 50° C. and 93% RH are shown in Figure 3. The relative humidity (RH) inside these packages with the different desiccants shows that the PAM begins to control humidity slower than the other desiccants, but as the test progresses the RH of the clay and silica gel packages exceeds that of the PAM-containing packages.

[0041] Rust prevention, moisture evaluation and weight gain evaluation confirmed that PAM acts as both a VCI and a desiccant.

[0042] Example 4 Three 0.1 cubic meter frames were constructed from extruded aluminum rod and each frame was placed inside a form-fitting 4 mil polyethylene (PE) bag. Three 1010 steel panels (Model R35 from Q panel Corporation) were draped inside each wrapped PE bag. High density polyethylene (Tyvek) containing 50 grams of high capacity desiccant (containing magnesium chloride and sodium polyacrylate) was placed inside the PE bag. (R) A sachet made from 90% PAM, 7% ammonium benzoate and 2.5% benzotriazole was placed inside one filled PE bag. A sachet containing 90% PAM, 7% ammonium benzoate and 2.5% benzotriazole was placed inside a second filled PERL bag. No VCI or desiccant was placed inside the third filled PE bag; it contained only the metal panel. The three PE bags were sealed, thereby creating a hermetic environment, and placed inside a walking chamber maintained at 100°F (38°C) and 98% RH for 27 days. The control showed corrosion on the first day and was completely corroded after two days. For panels in the first bag packaged with a MgCl-based desiccant, the first signs of corrosion occurred after 10 days, and by 20 days these panels were severely corroded. The metal panels inside the second bag with PAM showed no corrosion during the 27-day test period.

[0043] [Table 6]

[0044] Example 5 Electroless silver panels (a thin layer (5-15 μin) of silver deposited on the copper surface of a PCB board), brass parts, and electronic components containing copper and brass were hung inside two 9x12 inch bags. The bags were filled with 90% PAM, 7% ammonium benzoate, and 2.5% benzotriazole in high density polyethylene (Tyvek (R) A sachet (similar to the ) was placed inside one of the bags. The sachet was sealed to the top of the bag to avoid contact with metal parts. The second bag did not contain any VCI or desiccant. These filled bags were sealed and then SO 2 It was placed inside a chamber connected to gas and exposed to the following cycles: SO 2 8 hours at 30°C with 0.1L (approximately 300 ppm); 0.1L SO 2 8 h at 30 °C with 0.2 L SO 2 8 h at 38 °C with 0.2 L SO 2 with 0.4 L SO 2 with VCI for 8 hours at 45° C. After the fifth cycle, the brass, copper and silver parts in the bags with no desiccant or VCI showed significant corrosion, while no corrosion was visible on the parts that were in the bags with the PAM-containing blend.

[0045] While various aspects of the disclosure and what are presently believed to be certain preferred embodiments have been described, it will be apparent to those skilled in the art that changes and modifications may be made without departing from the spirit of the disclosure, and it is intended to include all such changes and modifications as fall within the true scope of the disclosure.

Claims

1. A volatile rust inhibitor composition comprising about 1% to about 100% by weight of polyacrylamide.

2. 10. The volatile rust inhibitor composition of claim 1 comprising from about 10% to about 100% by weight of polyacrylamide.

3. 3. The volatile corrosion inhibitor composition according to claim 1, wherein the polyacrylamide is crosslinked.

4. 3. The volatile corrosion inhibitor composition according to claim 1, wherein the polyacrylamide is linear.

5. 3. The volatile corrosion inhibitor composition according to claim 1 or 2, wherein the polyacrylamide is a homopolymer, a copolymer containing acrylamide, or a combination thereof.

6. The volatile corrosion inhibitor composition of any one of claims 1 to 5, further comprising up to about 99 wt.% of one or more second volatile corrosion inhibitors.

7. 7. The volatile corrosion inhibitor composition of claim 6, comprising up to about 90 wt.% of the one or more second volatile corrosion inhibitors.

8. 7. The volatile corrosion inhibitor composition of claim 6, wherein the one or more second volatile corrosion inhibitors are selected from the group consisting of: ammonium salts, triazoles, nitrites, nitrates, amine carboxylates, amines, carboxylic acids, aldehydes, acid anhydrides, and any combination thereof.

9. 7. The volatile corrosion inhibitor composition of claim 6, comprising from about 80% to about 90% by weight of polyacrylamide, and from about 1% to about 10% by weight of one or more second volatile corrosion inhibitors.

10. 7. The volatile corrosion inhibitor composition of claim 6, comprising from about 10% to about 20% by weight of polyacrylamide, and from about 70% to about 90% by weight of one or more second volatile corrosion inhibitors.

11. The volatile corrosion inhibitor composition according to any one of claims 1 to 10, wherein polyacrylamide is a volatile corrosion inhibitor and a desiccant.

12. The volatile corrosion inhibitor composition according to any one of claims 1 to 11, wherein the composition further comprises a deliquescent material.

13. The volatile corrosion inhibitor composition according to claim 12, wherein the deliquescent material is present in the volatile corrosion inhibitor composition in an amount of from about 1% by weight to about 50% by weight.

14. The volatile corrosion inhibitor composition according to any one of claims 1 to 13, wherein the composition is packaged in high density polyethylene fibers, nonwoven materials, paper, or polymeric films.

15. 1. A method for preventing rust on a metallic material, comprising: Providing metallic materials in a confined environment; Supplying the volatile corrosion inhibitor composition according to any one of claims 1 to 14 into the sealed environment; Including, The above method, wherein the volatile rust inhibitor composition prevents corrosion of a metallic material.

16. 16. The method of claim 15, wherein the volatile rust inhibitor composition is enclosed in a pouch or sachet, in a polymeric film, or coated onto a paper, foam, or porous substrate.

17. 17. The method of claim 15 or claim 16, wherein the volatile rust inhibitor composition is extruded into a monolayer or multilayer polymer film, injection molded into a part, or added to a liquid to form a gel or semi-solid medium.

18. 17. The method of claim 15 or claim 16, wherein the PAM in the volatile rust inhibitor composition absorbs moisture from the air and maintains a lower humidity environment compared to a system that does not have any desiccant.

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