New class of thermoplastic elastomer. Blend of HDPE and reclaimed rubber

In this research work TPE has been constructed by using High density polyethylene (HDPE) and Whole tire reclaimed rubber (RR). Optimized ratio of 50:50 HDPE: RR has been employed for the survey. Gamma irradiation and conventional chemical crosslinking with crosslinking coagent method were used to form a product. Results for gamma irradiation at 200KGy have been established for the best attributes.Waste management is an important issue of the 21st century. In India out of total waste generated every day; nearly 12-15% consists of polymeric waste. In this waste rubber content huge amount of itself due to growing automobile sector. It is hard to manage rubber waste as it’s not biodegradable and may be harmful to human organism. So the safe method is to reuse it as it is or by reclamation. Incorporation of this waste in the polymeric blends to form a thermoplastic elastomer (TPE) is the best way to utilize rubber waste. Thermoplastic materials like PE, PP, and PVC are cheap and widely available material to utilize for such determinations. The aim of project was to improve the overall properties of HDPE/ Reclaimed Rubber blend system and form a good example of new class of TPE. Blend of
HD and reclaimed rubber shows drastic enhancement in properties which can be used in automobile and other sectors.

Contents

1.0 INTRODUCTION

2.0 LITERATURE SURVEY
2.1 Recycling of Rubber Wastes:
2.1.1 Rubber recovery:
2.1.2 Why recovery or Reclaimation??
2.1.3 Rubber Reclaimation:
2.1.4 Advantages of using Reclaimed Rubber:
2.1.5 Rubber recycling by blending with plastics:
2.2 High Density Polyethylene (HDPE)
2.2.1 Toughening HDPE with elastomers:
2.3 Polymer Blend:
2.3.1 Thermoplastic Elastomers (TPE):
2.3.2 Classification of TPE:
2.3.3 Advantages and disadvantages of TPE:
2.4 Crosslinking Methods:
2.4.1 Peroxide crosslinking:
2.4.2 Radiation Crosslinking:
2.5 Need of Coagent:
2.5.1 Classification of coagent:
2.5.2 Coagent role in network formation:
2.5.3 Coagent Selection:

CHAPTER 3 EXPERIMENTAL
3.0 Experimental:
3.1 Raw Material:
3.2 Preparation of TPEs with varying HDPE & Reclaimed rubber ratio (SCHEME 1)
3.3 Preparation of TPEs with varying Triallyl Cyanurate (TAC) ratio (SCHEME 2):
3.4 Preparation of TPEs by Gamma Irradiation process with varying Triallyl Cyanurate (TAC) ratio (SCHEME 3):
3.5 Preparation of TPEs by Chemical crosslinking process with varying Triallyl Cyanurate (TAC) ratio (SCHEME 4):
3.6 TESTING PROCEDURES:
3.6.1 Mechanical Properties:
A. Tensile Strength:
B. Hardness (Shore D)
C. Charpy Impact Test:
3.6.2 Physical Properties:
A. Gel Content:
3.6.3 Thermal properties:
A. Differential Scanning Calorimetry (DSC) Test:
3.6.4 Rheological Analysis:
3.6.5: Morphological Analysis:

CHAPTER 4 RESULTS & DISCUSSIONS
4.0 Results & Discussions:
4.1 SCHEME 1:
4.1.1 Mechanical Properties:
A. Tensile Strength:
B. Hardness (Shore D):
C. Charpy Impact Strength:
4.1.2 Physical Analysis:
C. Gel Content:
4.1.3 Thermal Analysis
A. Differential Scanning Calorimetry (DSC) Test:
4.1.4 Morphological Analysis:
4.2 SCHEME 2
4.2.1 Mechanical Properties:
A. Tensile Strength:
B. Shore D Hardness:
C. Charpy Impact Strength:
4.2.2 Physical Analysis:
4.2.3 Thermal Analysis
A. Differential Scanning Calorimetry (DSC) Test:
4.2.4 Rheological Analysis:
4.2.5 Morphological Analysis:
4.3 SCHEME 3:
4.3.1 Mechanical Properties:
A. Tensile Strength:
B. Shore D Hardness:
C. Charpy Impact Strength:
4.3.2 Physical Analysis:
4.3.3 Thermal Analysis
A. Differential Scanning Calorimetry (DSC) Test:
4.3.4 Rheological Analysis:
4.3.5 Morphological Analysis:
4.4 SCHEME 4
4.4.1 Mechanical Properties:
A. Tensile Strength:
B. Shore D Hardness
C. Charpy Impact Strength:
4.4.2 Physical Analysis:
4.4.3 Thermal Analysis
A. Differential Scanning Calorimetry (DSC) Test:
4.4.4 Rheological Analysis:
4.4.5 Morphological Analysis

CHAPTER 5 CONCLUSION

5.0 Conclusion:

Part 1

Part 2

Part 3

Part 4

CHAPTER 6 REFERENCES
6.0 References

ABSTRACT:

Waste management is an important issue of the 21st century. In India out of total waste generated every day; nearly 12-15% consists of polymeric waste. In this waste rubber content huge amount of itself due to growing automobile sector. It is hard to manage rubber waste as it’s not biodegradable and may be harmful to human organism. So the safe method is to reuse it as it is or by reclamation. Incorporation of this waste in the polymeric blends to form a thermoplastic elastomer (TPE) is the best way to utilize rubber waste. Thermoplastic materials like PE, PP, and PVC are cheap and widely available material to utilize for such determinations. In this research work TPE has been constructed by using High density polyethylene (HDPE) and Whole tire reclaimed rubber (RR). Optimized ratio of 50:50 HDPE: RR has been employed for the survey. Gamma irradiation and conventional chemical crosslinking with crosslinking coagent method were used to form a product. Results for gamma irradiation at 200KGy have been established for the best attributes.

Keywords: Gamma irradiation, thermoplastic elastomers, Reclaimed rubber blends.

1.0 INTRODUCTION

One of the various problems which mankind faces as it enters into the 21st century is the problem of waste disposal management. Since polymeric materials do not decompose easily, disposal of waste polymers is a serious environmental problem. Large amounts of rubbers are used as tires for airplanes, trucks, cars, two wheelers etc. But after a long run when these tires are not serviceable and discarded, only a few grams or kilograms of rubber (1%) are abraded out from the tire. Almost the entire amount of rubber from the worn out tires is discarded, which again need very long time for natural degradation due to cross-linked structure of rubbers and presence of stabilizers and other additives. This poses two major problems: wastage of valuable rubber and disposal of waste tires leading to environmental pollution. Two major approaches to solve this problem are recycle and reuse of used and waste rubber, and reclaim of rubber raw materials. Reclaiming scrap rubber products is the conversion from a three dimensionally interlinked, insoluble and infusible strong thermoset polymer to a soft, plastic, tackier, low modulus, processable and Valcanizates essentially thermoplastic product. These methods can be classified as physical and chemical (Adhikari et al. 2000). In a physical reclaiming process, the rubber products are reclaimed with the help of external energy. The three dimensional network breaks down and the macromolecular rubber chain is transformed into small molecular weight fragments. The main physical reclaiming processes are: mechanical, thermo-mechanical, cryo-mechanical, and microwave and ultrasonic. On other hand chemical reclaiming is a growing process used for reclaimed rubbers manufacturers. The reclaiming agents are generally disulfides or mercaptans exclusively selected to work on high temperature. Since 1910 so many chemical reclaiming agents have been developed for natural and synthetic rubbers, such as diphenyl sulphide, dibenzyl disulphide, diamyl disulphide, bis(alcoxy aryl) disulphides, butyl mercaptans and thiophenolS, xylene thiols and phenol sulphides and disulphides (Pilar cases carne, 2000). Devulcanization methods make it possible to convert cured rubber into valuable products that can be reused as a replacement of virgin rubber in rubber compound. However, the quality of the devulcanized rubber is usually not good enough for the procedure to be widely applicable. Evidently for this reasons, only a small part of total waste is recycled via devulcanization (Dubkov K.A. et al. 2012).

One of the novel approaches can be choose as the utilization of this reclaimed rubber in thermoplastic polymeric material to form the thermoplastic elastomers (TPEs). The innovation of thermoplastic rubbers or elastomers (TPEs) in the late 1950s provided a new height to the field of polymer science and technology. A TPE is a rubbery material with properties and functional performance similar to those of conventional vulcanized rubber at ambient temperature, yet it can be processed in a molten state as a thermoplastic polymer at elevated temperature. (Schidrowitz et al. 1952, Tobolsky 1959, Legge et al. 1987, Walker et al. 1988) The unique characteristics of TPEs make them very useful and attractive alternatives to conventional elastomers in a variety of applications and markets, such as the automotive industry.

HDPE is one of the largest used commodity thermoplastic for industrial and household applications, its mechanical properties makes of it an ideal material for moulding applications products, moreover it is a 100% recyclable material. For the majority of applications HDPE is a tough polymer that doesn’t need further toughening. Nevertheless, there are numerous of applications under extreme conditions of strain rate and/or temperature for which its toughness needs to be substantially increased One way to increase toughness of polyethylene is by simple alterations of its chemical structure or another very common method is by blending it with rubbers (mostly with EPDM as rubber component). However, by adding rubber the tensile properties such as modulus and tensile strength decrease and, as more rubber is needed for the higher crystalline HDPE’s, it is a question whether in the end a better balance of properties is obtained (Pilar cases carne, 2000).

Apart from criterion like particle size distribution, temperature, etc. there would be the need of proper compatibilization system to form the miscible blend. The compatibilization could be occurs with the help of irradiation or chemical crosslinking system. Dispersion of elastomeric materials in thermoplastic material with irradiation system can enhance the crosslinking effect in properties of the blends with virtue of simple technique, pollution free atmosphere and fastening in time period. Irradiation of plastics is a way to induce cross-linking and to improve performances considerably. The expected compatibilization mechanism involves the formation of free radicals, leading to chain scission within rubber particles, crosslinking of polyethylene matrix and co-crosslinking between the two blend components at the interface when recycled HDPE blends with ground tyre rubber subjected to the gamma radiation. The blend itself does not contain any improvement in properties while the irradiation leads to the higher properties (Sonnier R. et al. 2006, Rouf O. Aly, 2012).

On other hand chemical crosslinking method was somehow called as older than irradiation one. There are number of chemical agents can be used as cross-linker for the same purpose, among which peroxides are the largest group of the family of the chemical crosslinking agent. Peroxides are capable of vulcanizing most of the polymer types, including standard unsaturated and saturated elastomer grades, fluoroelastomers and silicones. Irradiation system can be named as alternative process for chemical crosslinking method and vice-versa. While using both of these methods co-agent plays an important role in crosslinking enhancement (Henning S. 2004). Co-agents are multifunctional reactive compounds, which are used to enhance the peroxide crosslinking efficiency, thereby acting as a booster (Endstra 1991). However, there are clear differences in the efficiency with which certain coagent structures contribute to crosslink density based on cure chemistry and process. To realize the greatest improvements in a given application or cure type, it is crucial to understand the structure-property relationships directing coagent performance. The technology has progressed forward such that today the improvements in crosslink density are generally taken for granted, and coagent selection is now driven by the desire to improve more than just the modulus or tensile strength of the compound. (Henning S. 2004). Utilization of coupling agent like silane, titanate, etc. could possible for interfacial strengthening of material as pre-treatment to enhance the ease of processing and output of the products. Also on other side third component can be utilise to form a composites system with better enhancement in properties (Satapathy S. et al. 2009, Razmjooei F. et al. 2011 and Nabil A. et al. 2003).

In this research work the approach has been made towards the creating the blend system of High density polyethylene (HDPE) and Reclaimed rubber (RR) by compatibilizing it with both the peroxide and irradiation system (gamma radiation) with crosslinking co-agent Triallyl cyanurate. Comparative study has been made by observing the overall properties of the blend system using two different methods.

Aim & Objectives:

- Approach towards the rubber waste management issue by using reclaimed rubber in polymeric materials for better properties achievement to form a new class of TPE’s.
- To study the properties difference with differ in crosslinking methods.
- Enhance the mechanical properties of the HDPE/RR blend system.

2.0 LITERATURE SURVEY

2.1 Recycling of Rubber Wastes:

The management of rubber wastes is very difficult to municipalities to handle. The whole tires are difficult to landfill, because they tend to float to the surface. Stockpiles of scrap tires are located in many communities, resulting in public health, environmental and aesthetic problems (Yehia A. et al. 2012). The problem of recycling rubber has existed since Charles Goodyear first discovered vulcanization in 1839. Disposal of rubber into a landfill has become increasingly prohibitive due to high cost, legislative pressures, public opinion, especially high environmental stress. Researchers pay much attention to recycling. Many rubber products are now recycled such as used tires (Jinxia Li. 2008). Recently, the importance of recycling waste materials has been increasing for all industries worldwide. For rubber products, the automotive and transportation industries are the biggest consumers of raw rubber. Rubber waste is usually generated during the manufacturing process of products for these industries and by disposal of post-consumer (retired) products, mainly including scrap tires. For example, in Japan, about one million tons of scrap tires are generated annually (Fukumori et al.). Recycled involved processing used material into products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage and reduce air pollution by reducing the need of for conventional waste disposal. Recyclable materials include many kinds of glass, paper, metal, plastics, textiles and electronics. Several other materials are also commonly recycled, frequently at an industrial level. Tire recycling is also common. The interest in recycling of rubber has been increasing over the last decades. This has been driven by the concern over scrap tire and rubber products efforts on the environment. Since 2004 the Romanian government adopted a decision on management of used tires that includes collection and recovery of used tires, which has increased from 60% to the maximum recovery of 80% (Pusca Al. et al. 2010).

2.1.1 Rubber recovery:

Rubber recovery could be done in following ways:

- Rubber Reclaimation: the rubber waste is heated or frozen, treated with chemicals, and mechanically process.
- Pyrolysis: rubber waste is heated in absence of oxygen, causing decomposition into constituent parts and gases.
- Energy recovery: the rubber is burned in presence of oxygen, releasing energy, which is recovered to produce heat, electricity or steam (Ahmed R. et al. 1996)

2.1.2 Why recovery or Reclaimation??

Rubber recovery can be a difficult process. There are many reasons, however why rubber should be reclaimed or recovered:

- Recovered rubber can cost half that of natural or synthetic rubber.
- Recovered rubber has some properties that are better than those of virgin rubber.
- Producing rubber from reclaim requires less energy in the total production process than does virgin material.
- It is an excellent way to dispose of unwanted rubber products, which is often difficult.
- It conserves non-renewable petroleum products, which are used to produce synthetic rubbers.
- Many useful products are derived from reused tires and other rubber products.
- If tires are incinerated to reclaim embodied energy then they can yield substantial quantities of useful power. In Australia, some cement factories use waste tires as a fuel source (Abraham E. et al. 2011, Pusca Al. et al. 2010).

2.1.3 Rubber Reclaimation:

Reclaiming of scrap rubber is, therefore, the most desirable approach to solve the disposal problem. Reclaiming of scrap rubber products e.g. used automobile tires and tubes, hoses, conveyor belts etc is the conversion of a three dimensionally interlinked, insoluble and infusible strong thermoset polymer to a two dimensional, soft, plastic, tackier, low modulus, processable and vulcanizable essentially thermoplastic product simulating many of the properties of virgin rubber. Recovery and recycle of rubber from used and scrap rubber products can therefore, save some precious petroleum resources as well as solve scrap/waste rubber disposal problems. Many attempts have been made since 1910 for reclaiming of scrap rubber products. However, reclaiming process may be broadly classified into two groups: physical reclaiming processes and chemical reclaiming processes. In a review, Warner has summarized various methods of devulcanization using chemical and physical processes.

Reclaiming of rubbers by physical reclaiming processes

- In a physical reclaiming process scrap/waste rubber products is reclaimed with the help of external energy. Thus in physical reclaiming process three-dimensional network of cross-linked rubber breaks down in presence of different energy source. Due to the breaking of network structure macromolecular rubber chain is transformed into small molecular weight fragments so that it can be easily miscible with the virgin rubber during compounding. So reclaim rubber produced by physical reclaiming process may be used as non-reinforcing filler. But if in this process a specific amount of energy is used which is sufficient to cleave only the crosslink bonds then after reclaiming a good quality of reclaim rubber will be obtained which will b thermoplastic in nature and compare well with virgin rubber properties. Different types of physical reclaiming processes are: (i) mechanical (ii) thermo-mechanical (iii) cryo-mechanical (iv) microwave and (v) ultrasonic.

- Mechanical: In mechanical reclaiming process crumb rubber is placed in an open two-roll mixing mill and milling is carried out at high temperatures. In this process drastic molecular weight breakdown takes place due to mechanical shearing at high temperatures. In one patent by Maxwell et.al a physical process of reclaiming of vulcanized rubber and refining of the reclaimed rubber are described. The vulcanized rubber is particulate for (e.g. ground tire) is reclaimed with reclaiming agents by passing the rubber between essentially smooth stator and an essentially cylindrical rotor arranged to provide an axial shear zone is which the rubber is frictionally propelled by the rotor action. The action may be assisted by mixing suitable amount of previously reclaimed rubber or of vulcanized rubber with or in advance of the particulate vulcanized rubber, and/or by supplemental heating. In other aspects of the invention previously reclaimed and vulcanized rubber is similarly fed and acted upon as substitute for conventional refining operation. De and co- workers reported the mechanical reclaiming process of vulcanized NR. The reclaimed natural rubber was prepared by milling vulcanized sheets at about 808C. On a two roll laboratory mill it formed a band on the roll. Next, it was mixed with various rubber additives. In another case, mixing of reclaim rubber (RR) with fresh rubber in various proportions and study of their curing characteristics, mechanical properties etc. were done. But the Mooney viscosity o the reclaimed rubber was very high (.200, i.e. out of scale) indicating that the plasticity of rubber was very low due to the presence of higher percentage of cross-linked rubber. But the extents of reclaiming, parameters on the Mooney viscosity were not reported.

- Thermo-mechanical: This process involves the thermo-mechanical degradation of the rubber vulcanizate network. The vulcanizate is swollen in a suitable solvent and then transferred to a mill to form a fine powder (20 m diameter). This powder rubber is revulcanized with curing ingredients. The products thus obtained show slightly inferior properties to those of the original vulcanizates

- Cryo-mechanical: In the mid-1960s, the technique of grinding scrap rubber in cry mechanical process was developed. This reclaiming process involves placing small pieces of vulcanized rubber into liquid nitrogen which are transferred to a ball mill and ground in presence of liquid nitrogen to for a fine powder. The particle size of the cryo-ground rubber varies from 30 to 100 meshes for most products. The particle size is controlled by the immersion time in the liquid nitrogen and by the mesh size of screens used in the grinding chamber of the mill.

- Microwave Method: In the microwave technique a controlled dose of microwave energy at specified frequency and energy level in an amount sufficient to cleave carbon–carbon bonds is used. Thus in this process elastomer waste can be reclaimed without depolymerization to a material capable of being recompounded and revulcanized having physical properties essentially equivalent to the original vulcanizate This method is very much useful because it provides an economical, ecologically sound method of reusing elastomeric waste to return it to the same process and products in which it was original generated and it produces a similar product with equivalent physical properties. The devulcanized rubber is not degraded when the material being recycled which normally takes place in the usual commercial processes currently being practiced. In this process they claimed that sulfur vulcanized elastomer containing polar groups is suitable for microwave devulcanization. Tyler et al. have claim their microwave devulcanization process as a method of pollution controlled reclaiming of sulphur vulcanized elastomer containing polar groups. The microwave energy devulcanization device generate heat at a temperature in excess of 2608C to yield a mass which is fed to an extruder which extrudes the rubber at a temperature of 90–1258C. The extrudate can be used per se as a compounding stock. Another process was developed for reclaiming waste elastomers by microwave radiation. The process involve the impregnation of the waste rubber with an essential oil and then heat treating the impregnated material under reduced pressure with microwave radiation.

- Ultrasonic method: After the microwave techniques, ultrasonic energy was used for the devulcanization of cross-linked rubber. The first work with ultrasonic energy was reported by Pelofsky in 1973 which was patented in this process solid rubber articles such as tires is immersed into a liquid and then it was put with source of ultrasonic energy whereby the bulk rubber effectively disintegrated upon contact and dissolve into liquid. In this process ultrasonic irradiation is in the range of about 20 kHz and at a power intensity of greater than 100 W.

Reclaiming of rubbers by chemical reclaiming processes:

- The majority of the reclaim rubber industries use chemical reclaiming agents for the manufacture of reclaim rubbers. These are generally organic disulfides or mercaptans which are exclusively used during mechanical working at elevated temperature. Based on these chemicals many processes have been developed and subsequently patented. Apart from these a few inorganic compounds have also been tried as reclaiming agent (Adhikari et al. 2000, Pilar cases carne, 2000, Jinxia Li. 2008).

2.1.4 Advantages of using Reclaimed Rubber:

Although reclaim rubber is a product of discarded rubber articles it has gained much importance as additive in various rubber article formulations. It is true that mechanical properties like tensile strength, modulus, resilience, tear resistances etc. are all reduced with the increasing amounts of reclaim rubber in fresh rubber formulation. But at the same time the reclaim rubber provides many advantages if incorporated in fresh rubber.

- Easy breakdown and mixing time:

- During reclaiming process reclaimed rubber has already been plasticized due to a large amount of mechanical working, Therefore, in the consumer’s hands it mixes easily than new rubber at lower mixing time with less heat generation. This is particularly advantageous with compounds containing high carbon black loading. In the mixing of tire carcas and side wall stocks also this property is very advantageous because during first banbury pass reclaim rubber is not added rather added during second banbury pass along with the curing agents to a position of the master batch obtained from the first banbury pass. The second pass is much shorter than the first, therefore, an increase in mixing capacity of as much as 40% occurs with a 30% Banbury cost saving per pound of rubber. With increase in the ratio of reclaimed RHC to new RHC, the mixing cycle decreases. Furthermore, an all reclaim stock mixes in just one half the time required for an all new rubber stock.

- Low power consumption during breakdown and mixing:

Reclaimed rubber consumes less power during breakdown and mixing than new rubber. Rubber Reclaimers Association has done a series of experiments to study the power saving during mixing with reclaim rubber. The first series compared whole tire reclaimed rubber with natural rubber and SBR 1712. Each was mixed with black, filler and oil in proportions to stimulate the composition of the reclaim. Banbury time was kept constant. The savings in power cost per 1000 pounds of reclaim were: 20% vs Natural Rubber 34% vs SBR 1712. The second series show that a mixture of SBR 1712 and BR (without any additives) plus a small proportion of reclaim rubber shows 12% less power consumption than by SBR 1712 alone and 14% less power consumption than for the combination of SBR 1712 1 BR, the mixing time being constant in all the cases. The third series shows that SBR 1712 alone, and SBR 1712 plus increasing proportions of tire reclaimed rubber up to 50% on RHC basis, result in increasing power savings for a constant mixing time.

Advantages in calendaring & Extrusion:

Reclaimed rubber stocks can usually be processed at a lower temperature than those containing virgin rubber alone. It provides generally faster processing during extruding and calendering. Due to the presence of crosslinked gel in reclaimed rubber, it is less thermoplastic than new rubber compounds. Thus when extruded and cured in open steam they tend to hold their shape better. Extruder die swell and calender shrinkage reduce with a proper use of reclaim rubber due to its lower nerve. Fresh rubber calendered sheets show 6–10% shrinkage. Using of reclaim rubber in tire carcass stocks permits high speed calendering and results in smooth uniform coating. The use of substantial proportion of reclaim rubber in automobile floor mat stocks permits maximum calender speeds which is sometimes twice as large as when very high proportions of SBR are used. Reclaim rubber in tire carcass compound gives better penetration in the fabric and chord than a non-reclaim compound.

- Influence on tack behaviour:

- The tack of a non-reclaim compound may disappear within 24 h after calendaring whereas, reclaim rubber compound tend to maintain their tack longer than non-reclaim compound. Non-reclaim compounds become tackier in hot weather and dry in cold weather. On the other hand, reclaim rubber compounds are less influenced in tack variation in hot and cold weather. This characteristic of reclaim rubber is exploited for its usefulness in pressure sensitive tape.

- Cost and energy saving :

- Finally, it may be stated that incorporation of reclaim rubber into new rubber compound, not only reduces the cost of the finished product but also saves our united resource of fossil feed stock. Energy consumption in reclaim production from truck treads is 0.09 l of oil equivalent/kg and 0.12 l equivalent/kg from whole tire. These data show that negligible amount of energy in terms of oil equivalent is consumed for reclaim production. Energy consumption in the tire production is 25 l of oil equivalent/tire. But much less energy is consumed in the production and utilization of recycled rubber products than direct production of rubber articles from the virgin raw materials (Abraham E. et al. 2011).

2.1.5 Rubber recycling by blending with plastics:

The best way to recycle these rubber waste product by reclaiming and used it in rubber industry (Sadhan K.D. et al. 2005). The same rubber can be process with the material which has ability to flow under heat and pressure, so that it can be shaped into the useful articles at reasonable cost. This can be accomplished by mixing finely ground rubber with plastics, along with necessary additives (Jinxia Li. 2008). Thermoplastic plastics like PE, PP and PVC are not only cheap, but also available in a wide range of melt index and micro structure which can be used with recycled/reclaimed rubber. Also substantial commodity and engineering plastics are available from municipal waste Corporation. This can be used with plastics to form a new trend of polymeric blend which is known as thermoplastic elastomers and thermoplastic vulcanizates (TPEs & TPVs) (Sadhan K.D. et al. 2005, Jinxia Li. 2008).

2.2 High Density Polyethylene (HDPE)

Whether used in shopping bags, packaging materials, buckets, water pipers, gas mains, oil tanks, etc… HDPE (High Density Polyethylene) is present in day to day life applications. The worldwide demand for HDPE will grow by 4.4% to 31.3Mtons in 2009. The countries and regions primarily responsible for the growth will be: China (+8.5%), other Asian countries (+5%), Latin America (+5.9%), North America (+3.1%) and Europe (+2.8%) [Merchant Research & Consulting]. Hollow articles made with blow moulding processes are the most important application areas for HDPE. China, where HDPE bottles were launched in 2005, has experienced the fastest growing market for rigid HDPE packaging. India and other heavily populated markets, where infrastructures will continue to be built up, expect to have an increase of HDPE pipes and cables conductors. On the other hand, HDPE is gaining PVC (poly vinyl chloride) market share for being an environmentally friendly material.

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Details

• Grade: AB
• Authors: Prof. Mehul Patel (Author), Prof. Amar Arakh (Author), Prof. Pathik Shah (Author)
• Publication Year: 2014
• Pages: 91
• Catalog Number: V383428
• ISBN (eBook): 9783668610842
• ISBN (Book): 9783668610859
• Language: English
• Tags: blend hdpe