فهرست مطالب

صنعت لاستیک ایران - پیاپی 75 (پاییز 1393)

نشریه صنعت لاستیک ایران
پیاپی 75 (پاییز 1393)

  • تاریخ انتشار: 1393/10/27
  • تعداد عناوین: 13
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  • Z. Izadi, M. Razaghi, Kashani* Page 6
    Rubber products have many applications in the industry and their performances must be evaluated and optimized for different applications. One of these applications is tribological aspect of rubber compounds, especially friction and grip of tread vulcanizates on the road surfaces. Studies have shown that rubber friction is directly correlated to the dynamic loss tangent (tan δ). Reinforcing fillers and their various characteristics have strong influences on the viscoelastic properties of rubber including tan δ. The important point of all these characteristics is the ability of filler aggregates to trap and immobilize the rubber chains in their structure which has direct influence on reinforcement and improvement of the vulcanizate performance. Studies have shown that every changes in the filler characteristics which reduces the distance between the filler particles in the vulcanizates, will increase the amount of immobilized rubber and improves the vulcanizate performance. Some of these changes are increasing the volume fraction of filler, reducing the particle size, changing the particle shapes and surface modification of polar fillers such as silica. This article will review the mechanisms causing rubber friction on various surfaces, its relation to viscoelastic behaviour of vulcanizats, and the role of common particulate fillers such as carbon black and silica.
    Keywords: Reinforcing fillers, Nano, silica, Micro, silica, Tire, Linear viscoelastic properties, Tribological properties, Friction
  • H. Sadeghi Ghari*, Z. Shakouri Page 16
    Improving the performance of polymer products has always been considered by the researchers and manufacturers. By introducing nanotechnology to the polymer science, improving the properties and performance of polymer products such as plastics, rubbers and other types of polymeric products was intensified. In this regard, the use of nanoparticles for enhancing the mechanical performance of the rubbers has received more attention. But despite of many researches in the field of single filled polymer nanocomposites in the recent years, hybrid nanocomposites consists of several fillers are being investigated and not yet useable in the process. In this paper examines the performance of hybrid filler systems consist of nanoclay, carbon black, calcium carbonate, silica, carbon nanotube in rubber nanocomposites like NR, ENR, SBR, PU, BIIR, EPDM and NBR are discussed and a comparison between single-filler and hybrid filler nanocomposites was carried out. In this regard, greater focus on the morphology and mechanical properties and dynamic - mechanical properties of rubber nanocomposites were studied. For this purpose, the research conducted in the field of rubber nanocomposites in recent years which published by several researchers, their results are presented along with the scientific analysis and the favorable effect of these hybrid fillers on the performance of rubber products clearly displayed.
    Keywords: Nanocomposite, Nanoclay, Hybrid Filler System, Morphology, Mechanical Properties
  • R. Bagheri, M. Ranjbar* Page 28
    In recent years, rubber- metal composite material has attracted much attention in automotive industry and structural rubber. To have the best mechanical properties and high performance composites, strong rubber to metal bonding is necessary. Among these, structural composites made from natural rubber and steel because of increasing use in various industries, has academic attraction. Natural rubber to steel bonding can be done through hot bonding of rubber compound (containing material, that naturally tend to bond to the metal; such as Ebonite) via vulcanization, or by using a cold bonding of adhesiveprimer system, to bond cured rubber to steel. The mechanism of rubber to metal bonding using an interlayer of bonding agent (adhesive) is discussed with respect to various physical and chemical events such as adsorption at the metal surface, chemical crosslinking within the adhesive and primer, inter diffusion, and formation of interpenetrating networks at the rubber–adhesive interface. In this review, the natural rubber to steel bonding, simultaneously or after the vulcanization, is studied. In this approach, the basic formulation and adhesion promoter additives, based on natural rubber are presented; and then different techniques of natural rubber to steel bonding are discussed. Finally, the most important test to evaluate rubber to metal bonding resistance is introduced.
    Keywords: Rubber to metal bonding, Adhesion, Peels energy, Surface roughness, Natural rubber, Steel
  • F. Evaz, Malayeri* Page 40
    In this article, different kinds of masterbatches and their uses and benefits were introduced. Pigment or filler masterbatches, color masterbatches, additive masterbatches, accelerator masterbatches, sulphur masterbatches, antioxidant masterbatches, rubber compound materbatches and so on explained, and useful characteristics of masterbatches such as energy saving, increase quality of products, better handelling and less workforce, cleaner & safe workplace, less production time also mentioned.
    Keywords: Masterbatches, Filler masterbatches, Rubber compound materbatches
  • M. Ahmadi, Nazhad* Page 45
    Organizational intelligence is one of the components that should be possessed by the present era managers, in order to manage their subordinate organizations, by obtaining a deep knowledge. So, finding fields to improve staff motivation in order to fortify OI is an undeniable necessity. One of these fields is work design. The aim of this study is examination of the effect of job characteristics on OI in ministry of industry, mine and trade in Alborz province. The main means for collecting data included 2 standard questionnaires of the organizational intelligence by Albercht and job characteristics by Hackman and Oldham. Analyzing data has done by SPSS and in two levels: descriptive and inferential statistic. Results of the regression model showed that the variables of job characteristics has meaningful and positive effect on OI and also the role of growth need strength as moderate variable, in relation between work design and OI was confirmed.
    Keywords: Organizational intelligence, Work design, Job characteristics model, Growth need strength
  • M. Eftekhar*, A. Aslizadeh, M.M. Peidaei Page 58
    organizational commitment, motivation is one of the important issues which the identity of the person in the organization is, participation in the organization and it blends in and join enjoyed it and there are many reasons why an organization must increase its member's level of commitment. The commitment is a psychological state that indicates a desire, need and obligation to continue employment in an organization. This study aimed to determine the relationship between commitment organizational job performance among employees was to bark the tires. The study was based on objective, practical and descriptive in nature and is Using field studies to assess the existing situation. The statistical population includes all employees who are barking tires 1230 people. That among a sample of 292 is selected. Research instruments were organizational commitment, Meyer and Allen Paterson job function is used. The validity and reliability is calculated.
    Keywords: Organizational commitment, Job performance, Barking rubber company