MXPA00001748A - FAST SETTING WATER SENSITIVE POLYAMIDES HAVING A HIGH Tg - Google Patents

Abstract

The present invention relates to a fast setting water sensitive polyamide composition which is the reaction product of at least one reactant which is a dicarboxylic acid, ester or anhydride thereof and at least one reactant is a diamine wherein at least one of said diamines is polyoxyalkylene diamine and at least one of said other reactants is aromatic and said polyamide composition has a Tg of greater than about 15°C and a DH greater than 0 Joules/gram.

Description

POLYAMIDES SENSITIVE TO WATER OF FAST FIXATION THAT HAVE A HIGH THICKNESS DESCRIPTION OF THE INVENTION This invention relates to a hot melt polyamide composition sensitive to fast fixing water which is the reaction product of at least one dicarboxylic acid, ester or anhydride of the same and at least one diamine wherein at least one of the diamines is polyoxyalkylene diamine and at least one of the other reactants is aromatic. The resulting composition has a high vitreous transition temperature and a low melting heat. Polyamide polymers are useful in a variety of applications where water sensitivity is required such as for envelopes, stamps, packaging tapes, adhesive labels and labels. The particular feature that is required for these applications is rewettability. Rewettability refers to the ability of the adhesive composition to be activated through the use of water, for example. The adhesive composition is applied to a first surface or substrate, wetted and then attached to a second surface or substrate. For example, a postage stamp or shipping label can be applied in this form to an envelope.

In addition to rewettability, the adhesive composition may be capable of permanent fluctuations in temperature such as high ambient temperatures without undesired premature bonding of the coated substrates or premature bonding under ambient moisture conditions where the adhesive surfaces became sticky as a result of a lot of water absorption from the surrounding atmosphere. When pre-applied to substrates, eg labels, the adhesive should not block or tear the fiber prematurely when in storage under high temperatures and humidity conditions. Additional useful features of a hot melt adhesive include fast fixing speed, fast melt relationships and good machinability. The present inventors have discovered that superior properties can be achieved through the use of a polyamide that is semi-crystalline in character while retaining a high (Tg). The present invention relates to a water-sensitive polyamide composition which is the reaction product of at least one dicarboxylic acid, ester or anhydride thereof and at least one diamine in which at least one of the diamines is polyoxyalkylene diamine and At least one of the reactants is aromatic. The resulting composition is characterized as having a Tq greater than about 15 ° C, preferably greater than about 20 ° C, more preferably greater than about 25 ° C and more preferably greater than about 30 ° C, and a heat or melting or total heat ,? H, of greater than 0 joules per gram, preferably greater than 5 joules / gram, more preferably greater than about 10 joules / gram and more preferably greater than about 15 joules / gram. The present invention furthermore relates to a water-sensitive polyamide adhesive which is the reaction product of at least one aromatic dicarboxylic acid, the ester or anhydride thereof having the general formula: (C6H4) KR '[COOR] 2 wherein x is a number from about 1 to about 3, R 'is oxygen alkyl or substituted alkyl and R is hydrogen or an alkyl of 1 to 4 carbon atoms or an aromatic diamine; at least one polyoxyalkylene diamine having one of the following general formulas: H2N. { CH2) to [OCH2CH2] bO (CH2) aNH2 (I) wherein a is 1 to 3 and £ > it's 1 to 3; or _.H2 [CHR "-CH20] xCHR" CH2NH2 (II) wherein x is from about 2 to 5, and R "is hydrogen or an alkyl of 1 to 4 carbon atoms, or NH2CHR" 'CH2 [OCHR " 'CH2] C [OCH2CH2] d [OCH2CHR "'] eNH2 (III) wherein the sum of c + e varies from approximately 2 to about 8, d varies from about 12 to about 50 and R "'is an alkyl group of 1 to 4 carbon atoms; at least one aliphatic dicarboxylic acid, anhydride or ester thereof having from about 5 to about 36 carbon atoms and at least one aliphatic diamine having the following formulas: H2NCH2CH2CH (C2Hs) NH2 (I) and H2NCH2CH (CH3) (CH2 3NH2 (II) and H2N (CH2) XNH2 (III) wherein x is about 2 about 12. The present invention also relates to a water-sensitive polyamide adhesive which is the reaction product of about 15% to about 25% by weight of the reagents of an aromatic compound selected from the group consisting of aromatic dicarboxylic acids, anhydrides or esters thereof and aromatic diamines and mixtures thereof; from about 5% to about 30% by weight of at least one polyoxyalkylene diamine selected from the group consisting of those diamines having the general formulas: H2N (CH2) to [OCH2CH2] bO (CH2) aNH2 (I) wherein a is 1 to 3 and __ > it's 1 to 3; and NH2 [CHR "-CH2?] xCHR" CH2NH2 (II) wherein x is from about 2 to 5 and R "is hydrogen or an alkyl of 1 to 4 carbon atoms, and NHCHR" 'CH2 [OCHR "' CH2 ] C [OCH2CH2] d [0CH2CHR "'] eNH2 (III) wherein the sum of c + e ranges from about 2 to about 8, d varies from about 12 to about 50 and R"' is an alkyl group of 1 to 4 carbon atoms, from about 25% to about 35% by weight of an aliphatic dicarboxylic acid, anhydride or ester thereof having from about 5 to about 35 carbon atoms and from about 5% to about 25% by weight of the reagents of at least one aliphatic diamine having the following formulas: H2NCH2CH2CH (C2H5) N2 (I) and H2NCH2CH (CH3) CH2) 3NH2 (II) and H2N (CH2)? NH2"(III). wherein x is the number from about 2 to about 12. These polyamides are therefore characterized as being semi-crystalline or highly amorphous, as measured by a low ΔH and a high Tg. The compositions are further characterized as having a fast rate of fixation of less than about 5 seconds, and even less than about 1 second as measured by the amount of time it takes to become non-stick when the melt is applied to a thickness of approximately 1 thousandth film. The compositions also rewet much acceleration as the commercially available polyamides as measured by the amount of time it takes to develop the torn fiber after wetting the composition that has been applied to a first substrate and then applying it to a second substrate after the rewet The compositions are further characterized to have a melting point of less than about 200 ° C and preferably less than about 175 ° C. In the simple embodiment of the present invention, the water-sensitive polyamide composition is the reaction product of an aromatic dicarboxylic acid and a polyoxyalkylene diamine, the requirement being that it is some aromatic character and some aliphatic character in the resulting polyamide. The aromaticity raises the Tg and the aliphatic and aromatic combination results in a semicrystalline polyamide. In a second embodiment, a polyoxyalkylene diamine is reactive with an aliphatic dicarboxylic acid and the aromaticity can be supplied by an aromatic diamine. A third embodiment could include a polyamide which is the reaction product of an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid and a polyoxyalkylene diamine. The polyamide, in a fourth embodiment, could be the reaction product of an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid and an aliphatic diamine and a polyoxyalkylene diamine. Many combinations of at least one polyoxyalkylene diamine, aromatic dicarboxylic acids, esters of anhydrides thereof, aromatic diamines, aliphatic dicarboxylic acids and aliphatic diamines can be used. The main requirement is that there is at least one polyoxyalkylene diamine and at least one dicarboxylic acid. The aromaticity and the aliphatic character can be supplied in any way once the two aforementioned ingredients are presented. The present inventors imagine many possible combinations as long as the reactants provide some aromaticity and some aliphatic character to the resultant water-sensitive polyamide to obtain the high vitreous transition temperature and low heat or melt. The aromatic compounds useful herein are aromatic dicarboxylic acids, esters or anhydrides thereof or aromatic diamines. The aromatic dicarboxylic acids can have the following general formula: (C6H4) XR '[COOR] 2 wherein x is a number from about 1 to about 3, R' is oxygen, alkyl or substituted alkyl and R is hydrogen or an alkyl of 1 to 4 carbon atoms or an aromatic diamine having the following general formula: (C6H4) XR '[NH2] 2 wherein x is a number from about 2 to about 60 and R' is oxygen, alkyl or substituted alkyl. In a preferred embodiment, the dicarboxylic acid has x = 1 R 'is oxygen and R is a methyl group and has the formula (CHsH4) [COOCH3] and is otherwise known as dimethylterephthalate or DMT. Another preferred aromatic dicarboxylic terephthalic acid has the following formula: (C6H4) [COOH] 2 Other examples include isophthalic acid and t-butylisophthalic acid. Examples of useful aromatic diamines include ethylenedianiline (H2N (C6H4) CH2 (C6H4) H2N) available from BASF Corporation located in Parsippany, NJ and p-phenylenediamine (PPD) or 1, 4-benzene diamine (H2N (C6H4) H2N) available from Du Pont Specialty Chemicals in Wilmington, FROM. These aromatics raise the vitreous transition temperature, Tg, of the resultant polyamide compositions. These aromatics are useful from about 5% to about 50% by weight of the reactants, preferably from about 5% to about 45% by weight, more preferably from about 15% to about 35% by weight and more preferably about 15% to approximately 25% by weight of the reagents. The polyoxyalkylene diamines useful herein are those having the general formulas: H2N (CH2) a [0CH2HC2] b0 (CH2) aNH2 (I) wherein a is 1 to 3 and b is 1 to 3; and NH2 [CHR "-CH20] x CHR" CH2NH2 (II) wherein x is from about 2 to 5, and R "is hydrogen or an alkyl of 1 to 4 carbon atoms, and NH2CHR" 'CH2 [OCHR "' CH2] C [OCH2CH2] d [OCH2CHR "'] eNH2 (III) wherein the sum of c + e varies from about 2 to about 8, d ranges from about 12 to about 50 and R " 'is an alkyl group of 1 to 4 carbon atoms. Preferably the polyoxyalkylene diamine comprises ethylene oxide. An example is 4,7, 10- Trioxatridecan- 1, 13-diamine (TTD) available from BASF in Parsippany, NJ. From structure I above, when a = 2 and b = 1, the resulting structure is the Jeffamine® EDR-148 diamine available from Hunstaman Chemical Co. in Houston, TX; when a = 2 and b = 2 the resulting structure is Jeffamine® EDR-192 of Hunstman and when a = 3 and b = 2 1a the resulting structure is 4, 7, 10-Trioxatridecan-1, 13-diamine (TTD) available from BASF is Parsippany, NJ. In a preferred embodiment, the polyoxyalkylene diamine has the following formula: H2N-CH2CH2- [OCH2CH2] 2-NH2 (triethylene glycol diamine) available from the amine of Huntsman Chemical Co. in Houston, TX under the trademark of Jeffamine® EDR-148 mentioned above. Jeffamine® D series and ED series can also be used including Jeffamine® D-230, D-400, ED-600, DE-900 and DE-2001 all available from Huntsman. These polyoxyalkylene diamines can be used alone or in combination with other polyoxyalkylene diamines and are necessary to the water sensitivity of the resulting composition. These diamines are useful from about 5% to about 50% by weight of the reactants, preferably from about 5% to about 40% by weight and more preferably from about 5% to about 30% by weight of the reactants. Changing the molecular weight of the polyoxyalkylene diamine being used requires that the weight percent of the diamine reagent be changed, as well as to maintain the desired properties. The aliphatic dicarboxylic acids useful in the present invention are those having from about 5 to about 36 carbon atoms, esters or anhydrides thereof. These acids, esters or anhydrides generally have the following formula: (CH2) x [C00R] and wherein x is an integer from about 5 to about 36, R can be hydrogen or an alkyl group of 1 to 4 carbon atoms and is an integer of 1 or 2. Some examples of useful acids include adipic acid (x = 4, R is hydrogen and y = 2), a linear dicarboxylic acid having 6 carbon atoms. These acids are useful from about 5% to about 35% by weight of the reagents, preferably from about 15% to about 35% and more preferably from about 25% to about 35%.

The aliphatic diamines useful herein are those which can have the following general formula: H2N (CHR) XNH2 wherein x is a number greater than about 2 and R can be a hydrogen or an alkyl group having 1 to 4 carbon atoms . More specifically, useful aliphatic diamines having the following formulas: H2NCH2CH2CH (C2H5) NH2 (I) H2NCH2CH (CH3 (CH2) 3NH2 (II) and H2N (CH2) XNH2 (III) where x is the - number of about 2 to about 12. These aliphatic diamines are useful in amounts greater than about 5% by weight of the reagents, preferably from about 5% to about 25% by weight and more preferably from about 5% to about 15% by weight of the reactants. . a preferred embodiment, 2-methylpentamethylenediamine, available under the trademark of DYTEK® a Amine of Du Pont de Nemours &Co., is used Other useful aliphatic diamines include poly (alkylene) diamines having the following general formula: H2NCH ( CH3) CH2 [OCH2CH (CH3] X-NH2 wherein x is an integer from about 2 to about 3. Using a mixture of aliphatic and aromatic compounds reduces the crystallinity of the polyamide fi nal while the aromatic compounds help sustain a high Tg. This is a conjecture that it helps to improve the speed at which the resulting composition can be rewetted as well as decreasing the fusion speed. The present inventors contemplate that the other diamines that do not adversely affect the rewettability or other physical characteristics of the present invention and help reduce crystallinity can also be used in combination with the polyalkylene diamines. They can also be used to control the molecular weight of the polyamide composition. The monoamines and monocarboxylic acids can also be used in the compositions to control the molecular weight of the final product. An example of a useful monoacid is stearic acid, a linear acid having 18 carbon atoms and available from Henkel Corp., in Duesseldorf, Germany under the trademark Emerson® 132 and an example of a useful monoamine is stearylamine available from Akzo Nobel in Holland. These monoamines or monoacids are useful from about 0% to about 35% by weight of the reactants, preferably from about 0% to about 25% by weight and more preferably from about 0% to about 15% by weight. These mono functional components only affect the viscosity of the resulting polyamide and have been found to not affect the other characteristics. The resulting compositions are copolymers that typically have slower binding ratios than homopolymers. Surprisingly, the compositions of the present invention have a fast rate of fixation of less than about 5 seconds and even less than about 1 second as measured by the amount of time a film takes of approximately 1 thousand (25 / grams / square meters) ) thick to become non-sticky. This has been achieved by using semicrystalline or relatively amorphous polyamide compositions having a high Tg. Typically, quick fixation, non-viscous products are obtained with high crystallinity materials. The crystallinity of the products is measured by heating or melting or high heat,? H, which is greater than 0 Joules / gram, preferably greater than 1 joule / gram, more preferably from about 1 joule / gram to about 30 joules / gram. , more preferably greater than about 5 joules / gram, more preferably from about 5 joules / gram to about 30 joules / gram, more preferably greater than about 10 joules / gram, more preferably from about 10 joules / gram to about 25 joules / gram and more preferably from about 10 joules / gram, to about 20 joules / gram. It is necessary to the present invention that? H be greater than 0 joules / gram, but not 0 joules / gram because the final products may have some amount of crystallinity. It will be found that completely amorphous products are not useful for the present invention. While completely amorphous products can have the rewettability speed that is desirable, failing either to block the tests or to fix them slowly. In addition, they have low crystallinity that allows an excellent rewettability speed to be retained and are also allowed for excellent blocking resistance while retaining some crystallinity. The resulting polyamide compositions have high Tg's of greater than about 15 ° C, preferably greater than about 20 ° C, more preferably from about 20 ° C, to about 60 ° C, more preferably greater than about 25 ° C, more preferably from about 25 ° C to about 55 ° C, more preferably greater than about 30 ° C and more preferably about 30 ° C to about 55 ° C. It is a conjecture that the high Tg is more attributable to the introduction of aromaticity in the polyamide composition. Currently available products have Tg's of less than about 0 ° C. An elevated Tg is desirable to maintain a fast rate of fixation. Using the high Tg to maintain these properties instead of high crystallinity allows it to achieve a better balance between rewetting, blocking resistance and fixation speed than current compositions that are the state of the art. The compositions are further characterized as having melting points of less than about 200 ° C and preferably less than about 175 ° C. A fast fixing speed is important for fast application equipment such as extrusion equipment used in the packaging industry, as well as for coating equipment such as that used for coated labels, stickers, tapes, stamps and so on. The lower sticky surface, high melting point and high heat and moisture resistance is important for coating applications where the substrates are pre-coated and stored in tanks until use. These attributes help prevent premature bonding, or blockage of the adhesive where undesirable fiber tears or binds to other species of substrates. By blocking species where the substrates are stacked together, such as labels or adhesive labels, a label or adhesive label attaches the back of another label or adhesive label making the substrate undesirable. The lower sticky surface is also beneficial for coating applications where good die cut-off is desired. The resulting compositions are highly water sensitive or rewettable. These can be measured by the amount of torn fiber that can in turn tear in a short amount of time after adding wetting to the adhesive or coating. Rewettability is measured by the amount of time it takes to develop the torn fiber after wetting the composition that has been applied to a first substrate and then applied to a second substrate after rewetting. It is a conjecture that the low crystallinity of the final product improves the speed of rewetting. It is in the industry's practice to obtain rapid fixation velocity using high crystalline materials. The present inventors have found that it is much more advantageous to use semicrystalline materials with high Tg to obtain a fast fixing speed. The compositions of the present invention have better addition and rewet faster than the more crystalline commercially available products.

These compositions are useful as adhesives, coatings, as films and as non-woven fabrics, and can be used in any application where rewettability or water sensitivity is required. Some applications include adhesives and coatings for envelopes, stamps, packaging tapes, adhesive labels and labels. The compositions are also useful for construction and sealing for packaging materials such as cases, cartons and bags where the recycling of the containers is desired, for binding applications, for cigarette manufacturing, for roll packaging, central winding and adhesion of woven threads. These compositions can also be used for various applications in the manufacture of disposable articles. These compositions find particular utility in the non-woven industry. They can be useful for infant diapers and incontinent adult items including article construction, elastic joints, central stabilization, and fixation of superabsorbents, for medical garments, including curtains and surgical gowns and hospital pads. They can also be useful for feminine hygiene articles including construction adhesives and as garment bonding adhesives to secure a feminine towel to a underwear.

The compositions can also be used as unbonded woven films and materials in the production of disposable articles. Specific examples include the formation of a barrier film for nonwoven sanitary articles and diapers in which the composition is coated in line on a non-woven substrate and using the composition as a raw material for forming in-line non-wovens. These compositions can be applied using hot melt applicators of standard extrusion type including multi-bead extrusion and any type of coating equipment and methods including roll coating, die groove coating, non-contact groove coating, coating gravure, fibrillation and spray coating including spiral spray coating. The coating patterns are numerous and can be continuous or interrupted depending on the type of application and whether or not the composition acts as a film, coating or adhesive. The following non-limiting examples further illustrate the present invention. Examples The polyamides were prepared by known methods.

Test Methods 1. Rewettability This procedure is used to determine if a hot melt adhesive re-wettable after initial application gives an adequate bond when rewetting and binding to a particular substrate. A sample is heated to approximately 150 ° C and applied to white bond paper substrates using a 0.5 mil metal to lower the bar which was also heated to 150 ° C. The adhesive was then allowed to cool and the paper was cut into H inch strips. The thickness of the adhesive was measured with a micrometer to ensure that the coating was between about 0.6 mil and 1.0 mil. The adhesive was then conditioned at room temperature and 50% humidity for 2 hours. The H inch strips were then wetted with water at room temperature using an applicator to control the amount of moisture placed on the adhesive. Each strip was then immediately pressed into a second piece of white bond paper using the same amount of pressure as if enclosing an envelope. The test can be repeated using several moisture levels. A minimum of six samples were run for each moisture level used, and a control sample was tested at the same time. The torn fiber was calculated by 40% or more being excellent, good was between approximately 10% and 40% and poor teared fiber was less than 10% of the total bond. 2. Time Fixation After Moistening This is a test used to measure the amount of time needed for a sample for torn fiber after the addition of moisture and subsequent bonding to a second substrate. A film having a thickness of approximately 0.5 thousandths is coated on a standard white woven paper stock. Samples are cut into strips * s inch wide. The adhesive is then wetted with deionized water and adhered to a second standard uncoated white woven paper pulp and the amount of time required for the torn fiber is recorded. 3. Fixation Speed This test was used to measure the time, in seconds, during a 1 mil film to become non-sticky, after application to a paper substrate. The target range was less than 5 seconds and preferably less than 1 second. A downward heated bar was used to apply a 1 mil film using an application temperature of approximately 175 ° C. A stopwatch was started at the same time the adhesive was down. The time was observed in seconds, which I take for the adhesive to become non-sticky immediately by straining the adhesive with a cotton swab until the cotton fibers are not stacked to the adhesive. The number of seconds was observed. 4. Heat or Fusion or Total Heat,? H. The heats or Fusion were measured using a Method "of Test Standard ASTM 794-85, for Fusion Temperatures and Crystallization by Thermal Analysis.The sweep temperature was -40 ° C to 200 ° C. 5. Transition Temperature Vitrea, Ta. Vitreous transition temperatures were measured using ASTM D 3418-82 Standard Test Method, for Polymer Transition Temperatures by Thermal Analysis.The sweep temperature was -40 ° C to 200 ° C. ° C (85 ° F) / 90% RH This procedure is used to determine the blocking resistance of the polyamide composition under pressure, heat and / or humidity. 0. 5 mils thick is down on a standard white woven paper pulp of 8 ^ x 11 inches and dried in an oven at 135 ° C for about 1 minute. The adhesive specimen is cut into 1 inch wide strips.

A second 1 inch strip of standard, uncoated white woven paper stock is attached to the coated strip.

This combination is then placed between two carriers and a weight of 500 grams is placed in the carrier and the total assembly is then placed in a chamber at a temperature of approximately 30 ° C and a relative humidity of approximately 90%. After 24 hours, the samples were removed from the chamber and the uncoated paper pulp is removed from the coated pulp. The degree of torn fiber or adhesive peeled from the fibers is then recorded and each sample is calculated on a scale of 1 to 3, 1 being excellent without the torn fiber or light peeling, 2 is smooth / going through the peeling, but a minimum amount of torn fiber and 3 is broken in moderation to a heavy torn fiber. Comparative Examples A and B illustrate some current states of the art for re-wettable polyamide compositions. These examples illustrate compositions having high crystallinity and low Tg's. Example A shows good rewettability, but greater time fixation after rewetting. Example B also shows good rewettability and longer time fixation after rewetting and is also higher than the melting point. Example 1 exhibits a high Tg and an? H of about 17 joules / grams. This composition has a fast fixing speed while maintaining excellent re-wetting and blocking resistance. Example 2 demonstrates the effect of lowering the crystallinity as measured by? H. This maintains a fast rate of fixation, but has decreased blocking resistance and removes more slowly than Example 1. Example 3 demonstrates the effect of increasing the amount of crystallinity in the product as measured by? H. This example has a slightly slow rate of fixation as Example 1 and has excellent rewettability and blocking resistance. Comparative Examples C and D demonstrate the effect of eliminating the crystallinity, or in other words, these examples are completely amorphous. These compositions have good rewettability, but fail in blocking tests at 29 ° C and 90% relative humidity. Comparative Example E illustrates the effect of both having a high Tg and high crystallinity. This example exhibits excellent blocking resistance, but has inadequate rewettability characteristics.

Claims (11)

1. CLAIMS 1. A water sensitive polyamide composition which is the reaction product of at least one reagent comprising a dicarboxylic acid, ester or anhydride thereof, and at least one reagent comprising at least one diamine wherein at least one of the diamines is polyoxyalkylene diamine and at least one of the other reactants is aromatic and the polyamide composition has a T g greater than about 15 ° C and a DH of about 30 joules / gram.
2. 2. A water-sensitive polyamide composition which is the reaction product of: a) from about 15% to about 25% by weight of the reactants of at least one aromatic compound selected from the group consisting of aromatic dicarboxylic acids, their esters and anhydrides thereof, aromatic diamines, and mixtures thereof; b) from about 5% to about 30% by weight of the reactants of at least one polyoxyalkylene diamine selected from the group consisting of those diamines having the general formula: H2N (CH2) to [OCH2CH2] bO (CH2) aNH2 (I ) where a is 1 to 3 and ¿> it's 1 to 3; and NH2 [CHR "-CH20] xCHR" CH2NH2 (II) wherein x is from about 2 to 5 and R "is hydrogen or an alkyl of 1 to 4 carbon atoms, and NH2CHR" 'CH2 [OCHR "' CH2] C [OCH2CH2] d [0CH2CHR "'] eNH2 (III) wherein the sum of c + e varies from about
3. 2 to about 8, d ranges from about 12 to about 50 and R "'is an alkyl group of 1 to 4 carbon atoms from about 25% to about 35% by weight of the reactants of at least one aliphatic dicarboxylic acid , anhydride or ester thereof having from about 5 to about 36 carbon atoms, and a) from about 5% to about 25% by weight of the reactants and at least one aliphatic diamine, wherein the Tg of the resulting polyamide is greater than about 15 ° C and? H is greater than 0 Joules / gram 3.
4. The composition according to claim 1 or claim 2, characterized in that at least one of the reactants is an aromatic dicarboxylic acid. composition according to claim 1 or claim 2, characterized in that at least one of the reactants is an aliphatic dicarboxylic acid and at least one of the reactants is an aromatic diamine ica
5. 5. The composition according to claim 1 or claim 2, characterized in that at least one of the reactants is an aromatic dicarboxylic acid, ester or anhydride thereof having the following general formula: (C6H4) XR '[COOR] 2 in where x is a number from about 1 to about 3, R 'is oxygen, alkyl or substituted alkyl and R is hydrogen or an alkyl of 1 to 4 carbon atoms.
6. 6. The composition according to claim 5, characterized in that x is 1 and R is methyl. The composition according to claim 1 or claim 2, characterized in that the polyoxyalkylene diamine has the general structure selected from the group consisting of: H2N (CH2) to [OCH2CH2] bO (CH2) aNH2 (I) wherein a is 1 to 3 and b is 1 to 3; or NH2 [CHR "-CH20] xCHR" CH2NH2 (II) wherein x is from about 2 to 5, and R "is hydrogen or an alkyl of 1 to 4 carbon atoms, or NH2CHR" 'CH2 [OCHR "' CH2 ] C [OCH2CH2] d [OCH2CHR "'] eNH2 (III) wherein the sum of c + e ranges from about 2 to about 8, d varies from about 12 to about 50 and R"' is an alkyl group of 1 to 4 carbon atoms 8. The composition according to claim 1 or claim 2, characterized in that the Tg is greater than about 25 ° C and "H" is greater than about 10 joules / gram. claim 1, or claim 2, characterized in that the fixation rate is less than about 5 seconds 10. A method for using the composition according to claim 1 or claim 2, as a re-wettable adhesive or articles selected from the group consisting of envelopes, stamps, packaging tapes, labels and adhesive labels, comprising the steps of: a) applying a first substrate to the composition; b) wetting the composition; and c) applying a second substrate after wetting; wherein the composition develops at least 10% torn fiber from either the first substrate or the second substrate and has a fixation time after rewetting from about 5 seconds to about 30 seconds. 11. The method of using the composition according to claim 1 or claim 2, or in non-woven material.