Investigation of the effects of adhesion promoters on the adhesion properties of rubber/steel cord by a new testing technique

The effects of adhesion promoters, cobalt decanoate and PN759 (modified resorcinol) on the static and dynamic adhesion properties of rubber/steel cord in a carcass recipe are examined. A new testing method with special rubber/steel cord specimens was developed. It was found that cobalt decanoate could improve the static adhesion and favored the dynamic adhesion of rubber/steel cord so that adhesive failure mainly occurred in rubber phase. A resorcinol‐formaldehyde‐silica promoting system was deleterious to adhesion stability, but improved initial adhesion strength. PN759 improved the dynamic mechanical properties compared with resorcinol for the carcass vulcanizates at strains less than 10%. PN759 instead of resorcinol slightly improved the static and dynamic adhesion and the probability that adhesion failure occurred in the interphase was similar to that occurring in the rubber phase. The dynamic “pull‐out forces” for samples with 1.0 phr cobalt decanoate first increased and then decreased with the increase in the number of fatigue cycles and reached a maximum at 100,000 fatigue cycles. The covered rubber on the “pulled‐out” cord after fatigue appeared to form a screw thread form and the greater pull‐out force corresponded to more uniform and narrower screw threads. SEM images indicated that un‐dispersed filler agglomerates could be the initiating factor for adhesive failure. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39460.     

Enhanced interfacial adhesion of aramid fiber reinforced rubber composites through bio-inspired surface modification and aramid nanofiber coating

In order to improve the interfacial adhesion between aramid fiber (AF) and rubber matrix, a simple and facile method of aramid nanofiber (ANF) coating is demonstrated in this article. Tannic acid (TA) and polyethyleneimine (PEI) are polymerized in an alkaline solution to form a thin TA/PEI (TP) layer that is deposited on the surface of AF to introduce functional groups such as hydroxyl and amino groups. Then, the ANF coating is utilized to construct nanostructures on the surface of AF to improve the interfacial adhesion between the fiber and the rubber. Through hydrogen bonding and/or π-π stacking between the TP layer and the ANF, the ANF coating is firmly attached to the surface of AF. Compared with the untreated fiber, the interfacial adhesion of AF coated with ANF after 1, 3, 5, 7, 9 deposition cycles is increased by 27.8%, 29.1%, 31.5%, 43.1%, and 30.3%, and the mechanical properties of the fibers remain almost unchanged. This method shows its advantages of simple, facile, and time-effective, which is of great significance for industrial applications.     

Mechanistic investigation on moisture-induced softening of poly(vinyl acetate)-stiffened polyester fabrics

Softening phenomenon of fabrics stiffened with eco-friendly polymeric stiffening agents often occurs in service conditions, leading to a deteriorated stiffening style. It is highly desired to find the key factors that induce the softening of stiffened fabrics and to understand the softening mechanism. In this work, polyester fabrics and poly(vinyl acetate) (PVAc)-based stiffening agent were chosen as the typical fabrics and polymeric stiffening agent, respectively. The stiffness value, a sensitive style index for the stiffening effect of fabrics, was selected to evaluate the variation of fabric stiffening effect during storage. A phenomenon of rapid softening was observed in the fabrics stiffened with various amounts of PVAc-based stiffening agent. The stiffness value of stiffened fabrics decreased with the increase of hygroscopic amount. According to the hygroscopic kinetic data, the moisture-induced plasticization effect of stiffening agent film, and the detachment of stiffening agent film from the fibers caused by the moisture-induced weakening of interfacial interaction between the film and fiber, a possible softening mechanism of polymer-stiffened fabrics was proposed. The hygroscopic-drying cyclic experiments showed that the softening of stiffened fabrics was induced by the reversible plasticization effect and the irreversible interfacial damage between the film and fiber.     

Structure and adhesive properties of the RFL‐coated continuous basalt fiber cord/rubber interface

The relationships between the structure of the resorcinol‐formaldehyde‐latex (RFL) layer, static adhesion, and interfacial fatigue properties between the RFL‐coated continuous basalt fiber (CBF) cord and a rubber matrix were studied using films prepared from RFL systems with various formulas and H samples prepared with RFL‐coated CBF cord and NR/SBR matrix. Thermomechanical analysis and tensile testing of the RFL films were carried out using a dynamic mechanical analyzer (DMA). The H pull‐out force and fatigue properties were tested using a universal testing machine and an MTS, respectively. The interfacial fatigue life of the RFL‐coated CBF cord/rubber samples exhibited different variation regularity from the variation of the H pull‐out force as F/R and L/RF changed. The static adhesion reflected the connection strength between the cord and the rubber matrix, whereas the characteristics and the properties of the RFL layer played a decisive role in determining the damage rate of the adhesion. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44353.     

镀层对钢丝帘线与橡胶粘合性能的影响

研究高铜镀层(铜质量分数为0.670)和低铜镀层(铜质量分数为0.635)钢丝帘线与橡胶的粘合性能.结果表明,高铜镀层钢丝帘线与橡胶的初始粘合性能较好,但其老化后粘合性能下降明显;只要胶料配方合理,低铜镀层钢丝帘线与橡胶的初始粘合性能可接近高铜镀层钢丝帘线,而其老化后粘合性能明显优于高铜镀层钢丝帘线.     

Chemical treatments for improving adhesion between electrospun nanofibers and fabrics

Nanofiber‐coated fabrics have potential uses in filters and protective clothing. One major challenge is to ensure good adhesion of nanofibers to the fabrics achieving satisfactory durability against abrasion for practical use. This work is aimed to study adhesion mechanisms and their improvement between nanofibers and textile substrates; to achieve this goal cotton fabrics were treated with an alkali solution, while nylon fabrics were treated with ethanol. Adhesion of polyamide‐6 electrospun nanofiber layer to fabrics was evaluated by means of a peeling test. Treated fabrics showed improved bonding towards nanofibers: adhesion energy was ～0.58 J m^?2 for both untreated fabrics, and after treatments increased to 0.93 and 0.86 J m^?2 for cotton and nylon ones, respectively. Optical observations revealed that nanofibers deposited on fabrics are mainly linked to external protruding fibers (i.e., fabric hairiness). Therefore, surface hairiness seems to be the critical factor limiting adhesion. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39766.     

聚酯帘线与胶料粘合性能研究

研究不同预浸渍方法对聚酯帘线与胶料粘合性能的影响.结果表明,用水溶性环氧树脂和邻苯二甲酸酐或氯化亚锡作为预浸渍液,然后用RFL浸渍液处理聚酯帘线,帘线H抽出力比只用RFL浸渍液处理提高7～12 N;红外光谱分析表明,环氧树脂作为媒介与聚酯帘线表面及RFL胶层发生了化学作用;经两步浸渍处理的抽出帘线附胶量较大,粘合强度提高.     

Recent advances of natural fibers based green rubber composites: Properties,current status,and future perspectives

The searching of suitable alternatives to petroleum-based fillers is an uncompromising challenge in present day rubber research. Recently, natural fibers are the part of great attention of both academic and industrial researchers due to their easy availability, environmental friendliness, and biodegradability. Natural fiber is cellulose-rich material, which is preferentially used as alternative filler in rubber technology. This article reviews current advances in natural fibers filled rubber composites in terms of mechanical, thermal, and biodegradable properties (2010–2020). The incorporation of unmodified natural fibers as filler is not able to offer desired reinforcement in rubber composites. Several surface modification methods can be introduced to improve the overall performances of natural fibers filled rubber composites. Finally, the review clarifies present status and future prospects of natural fibers based advanced rubber composites in automobile industry. The successful designing of natural fibers based sustainable rubber composites can introduce a new era in green rubber technology.     

Mechanical and thermal properties of compatibilized polypropylene reinforced by woven doum

In this work, the development and the mechanical characterization of a doum textile composite based on a polypropylene matrix were carried out. Mechanical and rheological tests were effectuated, to illustrate the effect of woven fibers on the mechanical and viscoelastic properties at 0°, 15°, 30°, and 45° directions. The woven fibers were treated and the matrix was melted to a coupling agent to assure compatibility between the fibers and the polymer. The composites with long fiber are generally used as film and the main properties is the tensile. In this study, our goal was to improve the tensile properties. Results have shown that tensile properties exhibited a significant increase when compared to the polypropylene. However, it was observed that the stress direction has no influence on the thermal properties of the composite. Also, this article evaluates models that predict the stiffness of the composites at different stress directions to be compared to the experiments. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4347–4356, 2013     

Polymer adhesion in heat‐treated nonwovens

Polymer adhesion and sintering in compound nonwovens was studied. Nonwovens containing a mixture of binding bi‐component (BICO) fibers embedded in a fibrous matrix were heated to melt the outer shell of BICO fibers and interlock the matrix to create stiff load‐bearing surfaces. It was found that stiffness depends on heat‐treatment regimes. In low‐temperature regimes, BICO fibers melt, but do not fully flow and encase the surrounding filler matrix. At sufficiently high temperatures, the shells of BICO fibers melt and flow which results in encasing the neighboring filler fibers. This results in an abrupt increase in the nonwoven stiffness which is independent of heat‐treatment temperature. At significantly high temperatures, the filler matrix fibers sinter to each other leading to a further increase in stiffness. The experiments were conducted with co‐polymers frequently used in the shells of BICO to demonstrate the interlocking mechanism characteristic of these compound nonwovens. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46165.     

Effect of bonding systems and antioxidants on the adhesion between EPDM rubber and polyester fabric

Ethylene propylene diene monomer (EPDM) rubber mixes containing different types of bonding materials and various commercial antioxidants were used to evaluate the adhesion of EPDM rubber to polyester fabric. A new antioxidant was prepared by graft copolymerization of 1, 5-diaminonaphthalene (DAN) onto natural rubber (NR) in order to investigate its effect on adhesion. It was observed that EPDM mixes containing DAN grafted onto NR shows better adhesion levels than those containing commercial antioxidants. It is also clear that the new system has high resistance towards aging and ionizing radiation. The new NR-g-DAN acts not only to stabilize the rubber mix towards environmental conditions but also to improve adhesion to polyester fabric.     

Newsprint paper waste as a fiber reinforcement in rubber composites

The investigation of the economical use of lignocellulose waste, which is one of the environmental problems facing third‐world nations, is ongoing. In this study, we intended to increase the use of newsprint fibers in the rubber industry. For this reason, we treated newsprint fibers with sodium silicate and magnesium chloride, and we examined the water retention values and thermal degradation analyses of the treated fiber waste. The activation energy of degradation was evaluated with the Coats–Redfern method of analysis. The effects of the addition of different amounts [0–60 parts per hundred parts of rubber by weight (phr)] of untreated and treated newsprint fibers on both the electrical and mechanical properties of two different types of rubber (natural rubber and acrylonitrile rubber) were studied. This study led us to the conclusion that the addition of treated newsprint fiber waste at a concentration of 40 phr could lead to an end product characterized by good electrical and mechanical properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 469–478, 2004     

Cure characteristics and mechanical properties of short nylon fiber‐reinforced nitrile rubber composites

Acrylonitrile butadiene rubber (NBR)‐based composites were prepared by incorporating short nylon fibers of different lengths and concentration into the matrix using a two‐roll mixing mill according to a base formulation. The curing characteristics of the samples were studied. The influence of fiber length, loading, and rubber crosslinking systems on the properties of the composites was analyzed. Surface morphology of the composites has been studied using Scanning Electron Microscopy (SEM). Addition of nylon fiber to NBR offers good reinforcement, and causes improvement in mechanical properties. A fiber length of 6 mm was found to be optimum for the best balance of properties. It has been found that at higher fiber loadings, composites show brittle‐type behavior. Composites vulcanized by the dicumyl peroxide (DCP) system were found to have better mechanical properties than that by the sulfur system. The swelling behavior of the composites in N,N‐dimethyl formamide has been analyzed for the swelling coefficient values. Composites vulcanized in the DCP system were found to have higher rubber volume fraction than that in the sulfur system, which indicates better rubber–fiber interaction in the former. The crosslink densities of various composites were also compared. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1023–1030, 2004     

Improving adhesion properties between rubber compound and brass-plated steel cord by the addition of epoxidized natural rubber to rubber compound

The adhesion between a rubber compound containing epoxidized natural rubber (ENR) and a brassplated steel cord was studied to shed light on the role of ENR for the improvement of adhesion. The addition of ENR in the rubber compound caused cure rate to decrease, and as ENR loading increased, modulus and hardness increased while tensile strength and elongation at break decreased. An improvement of adhesion was obvious with low loading of ENR at the range of 2 phr, while an adverse effect was observed with higher concentrations of 10 phr. Since the ratio of sulfur to copper at the interphase of the rubber compound/brass film adhesion sample increases with increased ENR loading up to 2 phr, the acceleration of sulfide formation by ENR could be proven. Adequate curing of rubber and the formation of high-molecular layer at the interphase by addition of small amount of ENR improve adhesion. However, the toughening of the rubber caused by the addition of larger amounts of ENR degrades the adhesion due to the poor physical properties of the rubber compound.     

A comparative study of short nylon fiber—Natural rubber composites prepared from dry rubber and latex masterbatch

A novel method for the preparation of short nylon fiber–natural rubber composites was developed in which short fibers chopped to approximately 6 mm were incorporated in the latex stage and processed into sheet form. By this method, mixing cycle time was reduced without compromising the fiber dispersion. Fiber breakage during mixing was reduced. The new composites when compounded with a dry bonding system based on hexamethylenetetramine, resorcinol and hydrated silica (HRH) showed improved modulus, tensile strength and abrasion resistance compared to conventional composites. Tear strength, resilience, and compression set were similar to the conventional composites. SEM analysis indicated better interaction between matrix and fibers in the case of latex master batch. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

聚酯帘子线与橡胶粘合的研究进展

探讨了浸胶液在聚酯帘子线与橡胶之间的作用机理以及增粘作用。总结了聚酯一浴、二浴浸胶液、纺丝后加工浸胶处理、等离子体及共聚改性、纺丝技术的发展等对提高聚酯与橡胶粘接强度的影响。     

聚酯帘线与橡胶粘合技术的研究进展

从聚酯帘线的表面改性、间苯二酚-甲醛-胶乳（RFL）二次浸渍工艺、改性RFL一次浸渍工艺和胶料配方调整等方面介绍聚酯帘线与橡胶粘合技术的研究进展。聚酯帘线表面改性包括紫外光辐射和低温等离子体处理等;RFL二次浸渍工艺即先用化学方法将聚酯帘线表面活化或用特殊分散剂浸渍,再用RFL浸渍液处理;在普通RFL浸渍液中加入改性剂再进行浸渍处理,也可提高聚酯帘线粘合强度;还可通过调整胶料组成和采用不同增粘体系等方法提高聚酯帘线与橡胶的粘合性。     

Aramid pulp reinforced hydrogenated nitrile butadiene rubber composites with ionic liquid compatibilizers

Although carbon black is an effective reinforcement for most rubbers, its replacement by other fillers would be beneficial. Aramid fibers are used in a range of applications in the rubber industry, providing dimensional stability prior to vulcanization and improving the mechanical properties of the elastomeric product. Nevertheless, their relatively inert surface is an obstacle in the exploitation of their full potential. In this work, two ionic liquids were investigated as compatibilizers in the preparation of hydrogenated nitrile butadiene rubber composites with aramid pulp and carbon black fillers. The materials were characterized using swelling, hardness and tensile tests, differential scanning calorimetry, thermal gravimetric analysis, and infrared spectroscopy. The carbon black-free composite prepared from aramid pulp treated with 1.0 wt% of 1-carboxymethyl-3-methylimidazolium chloride outperformed all other studied materials, presenting a higher modulus at 100% strain (7.31 MPa), while maintaining high strain at break. Thus, ionic liquids were found to potentialize the aramid reinforcement effect in these rubber composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48702.     

浅谈橡胶与纤维骨架材料的粘合

介绍了橡胶和纤维骨架材料粘合的基本原理,讨论了直接粘合体系和浸渍体系的应用及原理,着重介绍了目前人造丝、尼龙、聚酯和芳纶等主要橡胶用纤维骨架材料所用的粘合体系的状况。     

Evaluation of cord/rubber adhesion by a new fatigue test method

Polymer adhesion and its evaluation are important from academic and industrial points of view. Today cords are used to reinforce rubber in various products. Cord–rubber adhesion can be evaluated using static and dynamic methods. The static methods are commonly used for qualification of raw materials. These methods are not suitable for prediction of durability of the cord/rubber system in real conditions. The dynamic adhesion tests (e.g., fatigue method) involve some important parameters to simulate the real conditions of cord/rubber composite usage. So they produce reliable results in comparison with static adhesion results. Increase in temperature of cord/rubber system occurs during utilization of product. Adhesion usually decreases with increasing temperature. So the static adhesion test (e.g., H‐pull test) results that are measured in the ambient temperature (23 ± 2°C) cannot be considered as the composite's performance in the utilization condition. Although heat build up occurs in the test samples during the fatigue test procedure, but this is not enough to illustrate the decreasing effect of the increased temperature on the results. The authors produced a heat chamber to improve the dynamic test. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2488–2494, 2006