NR breaker compound containing specific chlorotriazines as adhesion promoters.All commercially successful tires are now built as a series of layers of flexible high modulus See modulo. cords encased en·case tr.v. en·cased, en·cas·ing, en·cas·es To enclose in or as if in a case. en·case  ment n. in a low modulus rubber or
rubber like material, the cords in each layer being a given path or
direction and substantially equispaced and parallel (ref. 1). Steel
cords are used in most tires in the breaker breaker: see wave, in oceanography. and bead beadSmall object, usually pierced for stringing. It may be made of virtually any material—wood, shell, bone, seed, nut, metal, stone, glass, or plastic—and is worn or affixed to another object for decorative or, in some cultures, magical purposes. sections of the tire. Often the steel cord is coated with either zinc or brass, which is an alloy alloy (ăl`oi, əloi`) [O. Fr.,=combine], substance with metallic properties that consists of a metal fused with one or more metals or nonmetals. of copper and zinc, in order to improve the adhesion adhesion /ad·he·sion/ (ad-he´zhun) 1. the property of remaining in close proximity. 2. the stable joining of parts to one another, which may occur abnormally. 3. between the rubber article and the metal reinforcement reinforcement /re·in·force·ment/ (-in-fors´ment) in behavioral science, the presentation of a stimulus following a response that increases the frequency of subsequent responses, whether positive to desirable events, or . The choice of coating depends upon the nature of the rubber compound it is to be used in. The breaker stock usually utilizes brass coated steel cord with a copper content between 60-70%. The copper composition promotes adhesion because of the reaction between the copper and the elemental elemental emanating from or pertaining to elements. elemental diet see elemental diet. sulfur that takes place between the wire filament filament, in astronomy: see chromosphere. and the sulfur vulcanization vulcanization (vŭl'kənəzā`shən), treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and cold. bonds. Naturally, a vulcanization system rich in sulfur is required. A high sulfur to accelerator ratio is generally present. Since adhesion of the cord to the rubber material is critical, most rubber articles requiting good adhesion utilize natural rubber as the base polymer. Styrene-butadiene rubber and butadiene butadiene (by  t'ədī`ēn), colorless, gaseous hydrocarbon. There are two structural isomers of butadiene; they differ in the location of the two carbon-carbon double bonds in the rubber also show good adhesion,
but not to the degree of natural rubber. Bonding agents are often
incorporated into rubber compositions to promote adhesion and enhance
durability of the adhesive adhesive, substance capable of sticking to surfaces of other substances and bonding them to one another. The term adhesive cement is sometimes used in place of adhesive, especially when referring to a synthetic adhesive. bond between the rubber and the steel
reinforcement. Some such bonding agents are cobalt Cobalt, town, CanadaCobalt (kō`bôlt), town (1991 pop. 1,470), E Ont., Canada, NE of Sudbury, near Lake Timiskaming. Once a center for cobalt and silver mining, the area is now economically depressed. products, such as cobalt naphthenate and cobalt stearate stearate /ste·a·rate/ (ste´ah-rat) any salt (soap), ester, or anionic form of stearic acid. ste·a·rate n. A salt or ester of stearic acid. stearate any compound of stearic acid. , either alone or in combination with resorcinol resorcinol /re·sor·ci·nol/ (re-zor´si-nol) a bactericidal, fungicidal, keratolytic, exfoliative, and antipruritic agent, used especially as a topical keratolytic in the treatment of acne and other dermatoses. donors and HR additives, such as hexamethoxymethylmelamine. Another commercially available system which provides excellent adhesion between the rubber composition and the metal reinforcement is 2,3,5,6-tetrachloro-1,4-benzoquinone (TCBQ) in combination with a resorcinol donor. This article discusses two experimental adhesion promoters, 2-Chloro-4,6-bis(N-phenyl-p-phenylenediamino)1,3,5-triazine (WAP (1) (Wireless Access Point) See access point. (2) (Wireless Application Protocol) A standard for providing cellular phones, pagers and other handheld devices with secure access to e-mail and text-based Web pages. A) and 2,4-Dichloro-6-(N-phenyl-p-phenylenediamino)-1,3,5-triazine (WAP B), both of which have been shown to provide excellent adhesion in natural rubber and 80/20 NR/BR breaker compounds (ref. 2). This work, "Selected chloropyrimidines and chlorotriazines as wire to rubber adhesion promoters," (RW, Nov. 1990) demonstrated the excellent adhesion of these experimental compounds compared to several commercially available systems. This article discusses further work which has been done in the areas of compound optimization optimization Field of applied mathematics whose principles and methods are used to solve quantitative problems in disciplines including physics, biology, engineering, and economics. for systems containing these new compounds utilizing brass coated steel to natural rubber breaker compounds. The effectiveness of WAP A and WAP B as adhesion promoters in both unaged and several different aged environments will be demonstrated. Their effect upon the physical and dynamic properties of the compounds will be shown. An optimized compound will be recommended for use of these adhesion promoters. Adhesion of these compounds will also be shown in two new systems which demonstrate their effectiveness as adhesion promoters of zinc coated galvanized gal·va·nize tr.v. gal·va·nized, gal·va·niz·ing, gal·va·niz·es 1. To stimulate or shock with an electric current. 2. steel cable to natural rubber and NR/BR compounds, such as in a conveyor belt conveyor belt One of various devices that provide mechanized movement of material, as in a factory. Conveyor belts are used in industrial applications and also on large farms, in warehousing and freight-handling, and in movement of raw materials. application. The following list shows the abbreviations associated with the wire adhesion promoters (WAP) of this article and the commercial systems used for comparative purposes. WAP A: 2-Chloro-4,6-bis (N-phenyl-p-phenylenediamino)-1,3,5-triazine WAP B: 2,4-Dichloro-6- (N-phenyl-p-phenylenediamino) - 1,3,5 -triazine TCBQ: 2,3,5,6-tetrachloro- 1,4- benzoquinone CoSt: cobalt stearate CoN: cobalt naphthenate, 10.5% Co: cobalt boroacylate, cobalt content 22.5% R: resorcinol formaldehyde formaldehyde (fôrmăl`dəhīd'), HCHO, the simplest aldehyde. It melts at −92°C;, boils at −21°C;, and is soluble in water, alcohol, and ether; at STP, it is a flammable, poisonous, colorless gas with a suffocating resin R-A: resorcinol acetaldehyde acetaldehyde (ăs'ĭtăl`dəhīd) or ethanal (ĕth`ənăl'), CH3CHO, colorless liquid aldehyde, sometimes simply called aldehyde. It melts at −123°C;, boils at 20. condensation product (Chem.) a substance obtained by the polymerization of one substance, or by the union of two or more, with or without separation of some unimportant side products. See also: Condensation HMMM HMMM Hexamethoxymethylmelamine : hexamethoxymethylmelamine HMTA HMTA Hazardous Materials Transportation Act HMTA Hexamethylenetetramine : hexamethylenetetramine hexamethylenetetramine methenamine. NMP NMP New Millennium Program (NASA) NMP National Military Park (National Park Service) NMP N-Methylpyrrolidone NMP Network Management Protocol NMP Not My Problem : 2-nitro-2-methylpropanol Experimental Formulations and mixing procedures Several formulations were prepared. They are shown in several tables, all of which are referred to specifically in the discussion section of this article. All formulations are 100% natural rubber based, with the exception of the NR/BR recipe mentioned later. The masterbatches of each recipe, which include all components of the formulation except for the adhesion promoters and the vulcanization package, were prepared in a size IA internal mixer mixer, either of two electronic devices in which two or more signals are combined. In the type of mixer used in radio receivers, radar receivers, and similar systems, a signal is translated upward or downward in frequency. . The rubber was added at the beginning of the mix with the water on and the rpm setting at fast. Half of the carbon black was added and all the zinc oxide zinc oxide, chemical compound, ZnO, that is nearly insoluble in water but soluble in acids or alkalies. It occurs as white hexagonal crystals or a white powder commonly known as zinc white. was added at one minute. All other ingredients were added at three minutes "Three Minutes" is the 46th episode of Lost. It is the twenty-second episode of the second season. The episode was directed by Stephen Williams, and written by Edward Kitsis and Adam Horowitz. It first aired on May 17, 2006 on ABC. . The masterbatch was discharged at seven minutes after a sweep down at three and five minutes. The masterbatch was immediately milled and sheeted out. Except for the formulation in table 2, the adhesion promoters were added in a lab size internal mixer (300 cc Brabender head). All resorcinol and cobalt products were added at 120[degrees]C and mixed for three minutes to ensure good dispersion dispersion, in chemistry dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. . The crosslinking agents, such as TCBQ and HMMM, were added at 80[degrees]C along with the vulcanization package and were mixed for three minutes. The compounds were then milled and sheeted out to a thickness of 0.28 to 0.31 inches as specified by ASTM ASTM abbr. American Society for Testing and Materials D-2229 and ASTM D-1871 for adhesion pad construction and physical property evaluation. The formulation in table 5 was prepared by making a masterbatch in the mixer as described above. Subsequent mixes were made in a B mixer where the second stage mix was used to incorporate the resorcinol, cobalt and WAP products to a drop temperature of 120[degrees]C (about five minutes and a final mix was used to incorporate the curatives and remaining adhesion promoters to a drop temperature of 100[degrees]C (about three minutes). While WAP A and WAP B could have been added at either of the three mixes, the commercial adhesion promoters do not have this flexibility. Resorcinol products must be added at a higher temperature than the vulcanization package to ensure good dispersion. On the other hand, they may not be added at too high of a temperature as the resorcinol will fume fume Occupational medicine A solid suspension resulting from condensation of the products of combustion. See Inhalant Vox populi verbTo be in the midst of a mental mini-meltdown. . For this reason, resorcinol condensation products are sometimes used, such as R-A, to avoid the possibility of fuming fuming /fum·ing/ (fum´ing) emitting a visible vapor. fum·ing adj. Producing or emitting smoke or vapor, as for certain concentrated nitric, sulfuric, and hydrochloric acids. . The crosslinking agents, such as HMMM and TCBQ, must be added at a lower temperature mix as when the vulcanization package is incorporated into the rubber. While dispersion is very important, it is important not to mix these products for too long at an elevated temperature as they will begin to react with the rubber and the sulfur prematurely, therefore resulting in a poor adhesive bond between the rubber article and its metal reinforcement. An oscillating os·cil·late intr.v. os·cil·lat·ed, os·cil·lat·ing, os·cil·lates 1. To swing back and forth with a steady, uninterrupted rhythm. 2. disk rheometer rhe·om·e·ter n. An instrument for measuring the flow of viscous liquids, such as blood. (ODR ODR Online Dispute Resolution ODR On-Demand Routing ODR One-Definition Rule (C++) ODR Octal Data Rate (high speed memory interface transfers 8 bits of data per clock cycle) ODR Office of Dispute Resolution 2000) was used to evaluate the vulcanization characteristics of the compounds. The procedures employed were in accordance Accordance is Bible Study Software for Macintosh developed by OakTree Software, Inc.[] As well as a standalone program, it is the base software packaged by Zondervan in their Bible Study suites for Macintosh. to ASTM D-2084. The temperature at which cure meter data were collected and the cure temperature and time of cure are indicated in each table. Adhesion pad construction In adhesion pad construction, the procedures used were according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. ASTM D-2229 and ASTM D-1871. The brass coated tire cord used had a copper content of 67.5% for the study of tables 1 through 4 and figures 1 and 2. The remaining adhesion studies utilizing brass coated steel used cord with a copper content of 63.5%. Since a higher copper content is more beneficial to adhesion, a lower copper content was chosen to show that excellent adhesion may be obtained with WAP A and WAP B without the added expense of a high copper content brass coated steel tire The Steel Tire was awarded to the winner of the annual college football game between the University of Akron and Youngstown State University. The trophy comes from the main products of the two cities; Akron for its rubber and Youngstown for its steel. cord. The cord construction used was 2 x 2 x 0.25 mm. In the studies of tables 18-20, hot galvanized zinc coated 6 x 1 x 1.8 mm steel cable was used. Adhesion evaluations were conducted according to ASTM D-2229, "Adhesion of steel cord" with pull-out measure at 121[degrees]C. The pull-out force was measured using a Chatilion movable stage and a digital force gauge. The bottom grip held the block of rubber firmly in place. The bottom grip was mounted to a stage that lowered itself, exerting tension between the steel wire and the block in which it was embedded Inserted into. See embedded system. . The digital force gauge attached to the top grip that held the wire measured the force necessary to pull the wire from the rubber block. The embedded distance was 22.5 mm. The wire adhesion data for each sample shows the force in Newtons needed to pull the steel cord from the vulcanized vul·ca·nize tr.v. vul·ca·nized, vul·ca·niz·ing, vul·ca·niz·es To improve the strength, resiliency, and freedom from stickiness and odor of (rubber, for example) by combining with sulfur or other additives in the presence of heat pad at a rate of 50.8 mm per minute. The amount of rubber remaining on the wire after it was pulled from the rubber block is called percent coverage. It is rated on a scale of full coverage at 100% coverage to no coverage at 10% coverage. The wire coverage measurement is very significant in that it visually represents the adhesion of the rubber composition to the steel cord. The amount of rubber adhering to the cord after it has been pulled from the cured adhesion pad represents the relationship of the adhesive force attaching the rubber composition to the surface of the steel cord and the tear strength of the rubber itself. A large percentage of rubber coverage indicates that the adhesion to the steel cord exceeded the tear strength of the rubber itself. Several agings were performed on the adhesion blocks and on the test specimens Used to evaluate physical properties. Oven agings were performed in hot air circulating cir·cu·late v. cir·cu·lat·ed, cir·cu·lat·ing, cir·cu·lates v.intr. 1. To move in or flow through a circle or circuit: blood circulating through the body. 2. ovens for either two days at 121[degrees]C, three days at 100[degrees]C or two weeks at 70[degrees]C. Steam agings were performed at 100[degrees]C in a steam autoclave autoclave Vessel, usually of steel, able to withstand high temperatures and pressures. The chemical industry uses various types of autoclaves in manufacturing dyes and in other chemical reactions requiring high pressures. for three days. Salt agings were performed in 0.5M NaCi solution. The adhesion blocks were submerged 11.25 mm into this solution for seven days. Humidity humidity, moisture content of the atmosphere, a primary element of climate. Humidity measurements include absolute humidity, the mass of water vapor per unit volume of natural air; relative humidity (usually meant when the term humidity oven agings were performed at 90[degrees]C and 90% relative humidity relative humidity n. The ratio of the amount of water vapor in the air at a specific temperature to the maximum amount that the air could hold at that temperature, expressed as a percentage. for ten days. The retention of adhesion after agings in these environments is an indication of the stability of the chemical bonds formed between the rubber composition and the metallic reinforcements reinforcements reinforce npl (Mil) → renfort(s) m(pl) . Some adhesion promoters may give good adhesion in an unaged sample, but may show extreme degradation of the adhesive bond once it is exposed to heat, moisture, steam or salt. Retention of physical properties of the compound is also important. Since these formulations contain such high levels of sulfur, this is often difficult. WAP A and WAP B will be shown to have not only excellent adhesion and wire coverage in both unaged and aged environments, but will also demonstrate good physical properties in both unaged and aged conditions. Results and discussion Tables 1 and 2 illustrate the recipes used in the natural rubber breaker compound of a previous study. It is necessary to review these results in order to discuss the optimization work of this article. The cure meter results are shown in table 3. The physical properties are shown in table 4. The adhesion results are shown in figures 1 and 2. Both WAP A and WAP B demonstrate excellent adhesion and wire coverage compared to the control systems. Both are superior to the CoSt/RfNMP system. While WAP A and WAP B have better scorch safety than either control, their physical properties are clearly defensive. They both have very low modulus and high elongation elongation, in astronomy, the angular distance between two points in the sky as measured from a third point. The elongation of a planet is usually measured as the angular distance from the sun to the planet as measured from the earth. and tear compared to either control. Since a good breaker compound requires a high modulus, this needed to be corrected. A good breaker compound has several requirements. It must have a high sulfur content to obtain good adhesion to the metal reinforcement. Good heat, steam and salt aged adhesion is important. Good tack (green adhesion), good heat aged properties, good cut growth resistance, high modulus and low elongation are also other very important requirements. Two studies were undertaken to investigate these parameters. The first study, shown in tables 5-9, examines the effect of raising the sulfur level for WAP A and WAP B on adhesion and physical properties compared to three control systems. Tables 5 and 6 illustrate the recipe used. Note the variation in sulfur level between the control systems, which have not been changed from previous work discussed, and WAP A and WAP B. The TBBS TBBS The Bread Board System TBBS The Big Blue Sky (website) accelerator level was not increased because it is known that TBBS can be detrimental det·ri·men·tal adj. Causing damage or harm; injurious. det  ri·men to adhesion as it increases toward 1.0 phr.
Table 8 shows the physical properties of the compounds. WAP A exhibits
physical properties comparable to either of the three control systems at
both 4.0 and 5.0 phr sulfur. It has the same high modulus and low
elongation that the controls show. Tear, Die C and tensile strength tensile strengthRatio of the maximum load a material can support without fracture when being stretched to the original area of a cross section of the material. When stresses less than the tensile strength are removed, a material completely or partially returns to its are also comparable. At 4.0 phr sulfur, WAP B still has a high elongation and low modulus, tensile strength and shore A hardness. WAP B, while it demonstrates comparable tear and tensile strength at 5.0 phr sulfur, is still defensive in elongation and modulus. WAP A and WAP B at 4.0 and 5.0 phr sulfur demonstrate comparable adhesion and wire coverage to the control systems in unaged, aged two days at 121[degrees]C, and aged seven days in a 0.5M NaCI solution. They both demonstrate superior adhesion and coverage than all three controls after a three day steam autoclave aging at 100[degrees]C. While these results are good, it was felt that better adhesion characteristics could be obtained by using a different accelerator, specifically DCBS DCBS Department of Consumer and Business Services (Oregon) DCBS Department for Community Based Services . DCBS is N,N-dicyclohexyl-2-benzothiazylsulfenamide and is commonly used in compounds requiring good adhesion between natural rubber and a metal reinforcement. The study utilizing DCBS as the accelerator is an optimization study. The purpose of this study was to define the parameters necessary for obtaining good physical properties in a natural rubber breaker compound containing the experimental adhesion promoters of this article. Since WAP B was thought to be the hardest of the two WAPs to be optimized, it was used in the study. Three parameters were defined as having an effect on physical properties: carbon black type and amount, sulfur amount and accelerator amount. A statistically designed experiment was run with three variables at three different levels, resulting in 21 test cases. The study was performed twice; once with N330 carbon black and the second time with N351 carbon black. Carbon black level was evaluated at 50, 55 and 60 phr. Sulfur level was evaluated at 3, 4 and 5 phr. An 80% oiled sulfur was used for good dispersion. DCBS accelerator was evaluated at 0.35, 0.55 and 0.75 phr. The controls used are illustrated in table 10. Results were evaluated utilizing a computer program known as ECHIP, which statistically analyzes the data and allows one to generate contour contour or contour line, line on a topographic map connecting points of equal elevation above or below mean sea level. It is thus a kind of isopleth, or line of equal quantity. plots which illustrate the relationship between the variables in the experiment. Table 9 shows the recipe used. This recipe is the same as in table 1, except for the variation in carbon black, accelerator, and sulfur levels and/or type. Examining the results of the evaluation using N330 carbon black first, it was seen that carbon black level, sulfur level and accelerator level did not have a significant effect on tensile strength or tear resistance. However, at the high level of sulfur, 5.0 phr, it was seen that accelerator level and carbon black level did affect elongation and modulus levels. The effects are linear. With increasing levels of accelerator, carbon black and sulfur, the modulus is seen to increase. These results indicate that the optimum point in the study for WAP B compared to the controls will be obtained by using 5.0 phr sulfur, 0.7 phr DCBS and 58.0 phr. Some of the specific test cases are illustrated in tables 11 and 12, showing the cure meter data at 160[degrees]C and unaged physical properties, respectively. Notice that with higher levels of sulfur, the cure time to optimum is longer. This can be shortened short·en v. short·ened, short·en·ing, short·ens v.tr. 1. To make short or shorter. 2. somewhat with an increase in accelerator level. The scorch times are similar between the test cases containing WAP B and the controls. The test case containing 60.0 phr N330 carbon black (B) compared to the test case containing 50.0 phr carbon black (A) even has a higher minimum and maximum torque at the same accelerator and sulfur levels because of the increased filler fill·er 1 n. One that fills, as: a. Something added to augment weight or size or fill space. b. A composition, especially a semisolid that hardens on drying, used to fill pores, cracks, or holes in wood, plaster, level. The same evaluation was carried out using N351 carbon black. Tensile strength was not significantly affected by the change in either parameter (1) Any value passed to a program by the user or by another program in order to customize the program for a particular purpose. A parameter may be anything; for example, a file name, a coordinate, a range of values, a money amount or a code of some kind. . Shore A hardness was only affected by sulfur and carbon black level. Once again the effects seen were linear. Tables 13 and 14 show some of the specific test cases and their related cure meter data at 160[degrees]C and unaged physical properties, respectively. The study again pointed out that the optimum level of DCBS accelerator, sulfur and carbon black was 0.7, 5.0 and 58.0 phr respectively. This is shown in table 15. As a follow-up to these two studies, both WAP A and WAP B were evaluated in the compound of table 15 using both N330 and N351 carbon black. The three control systems remained the same, utilizing 50.0 phr N330 carbon black, 0.55 phr DCBS and 3.25 phr sulfur. In this study all the test cases were cured for twenty minutes at 160[degrees]C. This brought them all to optimum cure. Cure meter data are shown in table 16. Unaged physical properties are shown in table 17. Both WAP A and WAP B show higher modulus with the more reinforcing carbon black, N351. WAP A properties are comparable to the control systems with the use of the N351 carbon black. WAP B has comparable properties with either N330 or N351. After aging for three days at 100[degrees]C and two weeks at 70[degrees]C, the physical properties of both WAP A and WAP B using either N330 or N351 are comparable to the three control systems. Examining the control systems, the weakest system is the CoSt system. The TCBQ/R-A system and the Co/HMMM/R both perform comparative to each other overall in force necessary to remove the wire from the rubber block. TCBQ/R-A had better unaged and two day oven aging adhesion than the Co/HMMM/R system. The Co/HMMM/R system had better adhesion after steam aging than the TCBQ/R-A system, however. Looking at wire coverage, the TCBA/R-A system had the best coverage of the three control systems. Turning to the experimental adhesion promoters WAP A and WAP B, both exhibit good overall adhesion in unaged and aged conditions compared to the controls. They were superior to the CoSt system under all conditions. WAP A, with N330 carbon black, had comparable adhesion to the TCBQ/R-A system. WAP A, with N351 carbon black, was comparable or superior to the Co/HMMM/R system in both force measurements and in wire coverage. WAP B also had comparable adhesion to the TCBQ/R-A and Co/HMMM/R systems. WAP B, with N330 carbon black, had better wire coverage than with the N351 carbon black. Its wire coverage was superior to both of the control systems. WAP A and WAP B were evaluated as adhesion promoters of zinc coated galvanized steel cable to natural rubber and NR/BR compounds. The first evaluation to be discussed is the 100% natural rubber compound. Tables 18 and 19 show the compound formulation, control system and the experimental systems evaluated. Table 20 shows the cure meter data at 145[degrees]C. Compounds were cured to Tc90 + two minutes. Both WAP A and B were evaluated alone, in combination with resorcinol and HMTA, and in combination with the three component system of Co/R/HMTA. Both WAP A and WAP B demonstrated very poor adhesion to the steel cable when evaluated at 2.0 phr alone in the compound. However, when WAP A is used in combination with HMTA and resorcinol, its adhesion is improved. It is not yet comparable to the control though. WAP A in combination with HMTA, resorcinol and the cobalt boroacylate compound showed good adhesion with slightly better adhesion after heat aging. WAP B in combination with HMTA and resorcinol showed good adhesion and wire coverage, although still defensive to the control system. However, when used in combination with HMTA, resorcinol and the cobalt boroacylate, this four component system exhibited better adhesion and much superior wire coverage than the control system. This is especially critical in the aging at 145[degrees]C in the press for 225 minutes. This aging is meant to simulate simulate - simulation an overcure situation that would occur in the field during conveyor belt construction. The last compound of this article is a proprietary 80/20 NR/BR compound with a high silica silica or silicon dioxide, chemical compound, SiO2. It is insoluble in water, slightly soluble in alkalies, and soluble in dilute hydrofluoric acid. Pure silica is colorless to white. loading and a sulfur cure system. Adhesion to 6 x 1 x 1.8 mm steel cable was tested. WAP A and WAP B were evaluated in combination with HMMM and resorcinol. Both demonstrate superior unaged and aged adhesion and coverage to the three component control system of a cobalt product, HMMM and resorcinol. Examining the physical properties one can see that PFDO PFDO Platform Forward Door Opened PFDO Pittsburgh Flying Disc Open (tournament) provides a compound with similar physical properties to the control system. WAP A provides a compound with higher modulus and hardness and a lower elongation. Conclusions WAP A showed excellent adhesion to 63.5% copper containing brass coated tire cord and physical properties in the natural rubber compound containing 0.5 phr TBBS and 4.0 phr sulfur compared to the control systems. It is recommended that a soluble soluble /sol·u·ble/ (sol´u-b'l) susceptible of being dissolved. sol·u·ble adj. Capable of being dissolved, especially easily dissolved. sulfur, such as the 80% oiled sulfur used in the studies of this article, be used since solubility solubility Degree to which a substance dissolves in a solvent to make a solution (usually expressed as grams of solute per litre of solvent). Solubility of one fluid (liquid or gas) in another may be complete (totally miscible; e.g. and dispersion of such high levels of sulfur is extremely important in obtaining good adhesion. In the natural rubber compound containing DCBS accelerator, the optimized system for WAP A compared to the control systems is 0.7 phr DCBS, 5.0 phr sulfur and 58.0 phr N351 carbon black. In this combination, WAP A at 2.0 phr demonstrated good overall adhesion in unaged and aged conditions compared to the controls. It was superior to the CoSt system under all conditions. WAP A, with N351 carbon black, was comparable or superior to the Co/HMMM/R system in both force measurements and in wire coverage. WAP B showed excellent adhesion to 63.5% copper containing brass coated tire cord and physical properties in the natural rubber compound containing 0.5 phr TBBS and 5.0 phr sulfur compared to the control systems. In the natural rubber compound containing DCBS accelerator, the optimized system for WAP B compared to the control systems is 0.7 phr DCBS, 5.0 phr sulfur and 58.0 phr N330 carbon black. In this combination, WAP B's excellent overall adhesion in unaged and aged conditions compared to the controls. WAP B, with N330 carbon black, had better wire coverage than with the N351 carbon black. Its wire coverage was superior to both of the control systems. The use of WAP A and WAP B as adhesion promoters of natural rubber to brass coated cord is especially advantageous over the control systems in that it is a one component system. The control systems were either two or three component systems. Another advantage of WAP A and WAP B is that they may be incorporated into the rubber during high or low temperature mixing. There is no need to worry about mixing at a higher temperature for better dispersion, premature crosslinking if mixed at a high temperature, or fuming at high temperatures as one must if any of the control systems are used. WAP A and WAP B allow one to totally eliminate resorcinol products from the compound. This is a definite benefit, since the tire industry seems to be moving this way. WAP A and WAP B, while not providing good adhesion of natural rubber or NR/BR to galvanized steel by themselves, can provide improved adhesion and much better wire coverage when used in combination with all or part of the typical adhesion systems used, consisting of a cobalt product, resorcinol and a crosslinking agent like HMMM or HMTA. References 1. V.E. Gough in "Mechanics of the pneumatic tire Noun 1. pneumatic tire - a tire made of reinforced rubber and filled with compressed air; used on motor vehicles and bicycles etc pneumatic tyre bicycle wheel - the wheel of a bicycle ., 2nd edition," S.K. Clark, ed., U.S., p. 216. 2. Seibert, Rebecca F., "Selected chloropyrimidines and chlorotriazines as wire to rubber adhesion promoters." Rubber World, November, 1990.
Table 1 - natural rubber wire breake compound
SMR 5CV 100.0
Carbon black N330 55.0
Zinc oxide 7.0
Stearic acid 2.0
Naphthenic oil 6.0
Antidegradant[sup.a] 2.0
Adhesion promoters as indicated
TBBS[sup.b] 0.5
Sulfur, 80% oiled 4.0
[sup.a]N-13-dimethylbutyl-[Nsip.i]-phenyl-p-phenylenediamine
[sup.b]N-t-]butyl-2-benzothiazole sulfenamide
Table 2 - natural rubber wire breaker compound:
adhesion systems
CoSt/ TCBQ/
R/NMP R-A WAP A WAP B
NR masterbatch 172.0 172.0 172.0 172.0
Cobalt stearate 1.0
Resorcinol resin 2.0
Nitromethylpropanol 2.0
KVDA[sup.a] 2.0
PFDO[sup.b] 2.0
TCBQ[sup.c] 1.0
R-A[sup.d] 2.0
[sup.a] 2-Chloro-4 6-bis(N-phenyl-p-phenylenediamino)-1,3,5-triazine [sup.b] 2,4-Dichloro-6-(N-phenyl-p-phenylenediamino)-1,3,5-triazine [sup.c] 2,3,5,6]-Tetrachloro-1,4-benzoquinone [sup.d] Resorcinol-acetaldehyde condensation product
Table 3 - select chlorotriazines in NR breaker
compound: cure meter at 150[degrees]C
CoSt/ TCBQ/ WAP A WAP B
R/NMP R-A
ML, Nm 0.87 1.14 0.74 0.78
MHF, Nm 3.11 3.95 4.13 2.84
Ts1 3.0 3.5 4.9 6.6
[t.sup.i]c25 6.5 6.3 7.5 10.0
[t.sup.i]c50 9.9 9.6 9.0 12.0
[t.sup.i]c90 22.0 22.2 15.2 25.9
Compounds cured to tc90 + 2 minutes
Table 4 - chlorotriazines in NR breaker
compound: physical properties
CoSt/TCBQ/WAP A WAP B
R/NMP R-A
Tensile strength, MPa 22.0 20.9 21.8 21.8
300% Modulus, MPa 16.1 18.7 11.7 10.7
Elongation, % at break 400 320 480 550
Tear, die C, kN/m 87.6 75.3 99.8 84.1
Shore A hardness 75 66 70 66
Compounds cured to tc90 + 2 minutes at 150[degrees]C
Table 5 - natural rubber wire breaker compound
SMR 5CV 100.0
Carbon black N330 58.0
Zinc oxide 7.0
Stearic acid 2.0
Naphthenic oil 6.0
antidegradant[sup.a] 2.0
Adhesion promoters as indicated
TBBS[sup.b] as indicated
Sulfur, 80% oiled as indicated
[sup.a]N-13-dimethylbutyl-[N.sup.i]-phenyl-p-phenylenediamine
[sup.b]N-t-butyl-2-benzeothiazolesulfenamide
Table 9 - natural rubber wire breker compound adhesion systems
SMR 5CV 100.0
Carbon black as indicated
Zinc oxide 7.0
Stearic acid 2.0
Naphthenic oil 6.0
Antidegradanta 2.0
WAP B 2.0
DCBS[sup.b] as indicated
Sulfur, 80% oiled as indicated
[sup.a]N-13-dimethylbutyl-[N.sup.i]-phenyl-p-phenylenediamine
[sup.b]N-t-butyl-2-benzxothiazole sulfenamide
Table 10 - control systems for optimization
CoSt/ TCBQ/ Co/R/
R/NMP R-A HMMM
NR masterbatch 172.0 172.0 172.0
Cobalt stearate 1.0 -
-Cobalt naphthenate - - 1.0
Resorcinol resin 2.0 - 2.5
R-A - 2.0
-Nitromethylpropanol 2.0 -
-TCBQ - 1.0
-HMMM - - 2.5
Cured at 160[degrees]C to Tc90 + 2 minutes.
Table 15 - optimized recipe for WAPs
SMR 5CV 100.0
Carbon black N330 or N351 58.0
Zinc oxide 7.0
Stearic acid 2.0
Naphthenic oil 6.0
Antidegradant[sup.a] 2.0
WAP A or WAP B 2.0
DCBS[sup.b] 0.7
Sulfur, 80% oiled 6.25
[sup.a]N-13-dimethylbutyl-[N.sup.i]-phenyl-p-phenylenediamine
[sup.b]N-t-Butyl-2-benzothiazole sulfenamide
Table 18-natural rubber
conveyor belt compound
SMR 5CV 100.0
Carbon black N660 50.0
Naphthenic oil 3.0
Stearic acid 1.0
Zinc oxide 20.0
Antidegradant[sup.a] 2.0
Adhesion promoters As
indicated
DTDM[sup.b] 0.8
CBS 0.6
Sulfur 2.5
Lead oxide 2.0
[sup.a]N-1,3-dimethylbutyl-[N.sup.i]-phenyl-phenylenediamine
[sup.b]4,[4.sup.i]-dithiodimorpholine
[TABULAR tab·u·lar adj. 1. Having a plane surface; flat. 2. Organized as a table or list. 3. Calculated by means of a table. tabular resembling a table. DATA OMITTED References 1. V.E. Gough in "Mechanics of the pneumatic tire, 2nd edition, "S.K. Clark. ed., U.S., p. 216. 2. Seibert, Rebecca F. "Selected chloropyrimidines and chlorotriazines as wire to rubber adhesion promoters," Rubber World. November, 1990. |
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