Dynamically Vulcanized PP/EPDM Blends: Effects of Different Types of Peroxides on the Properties

2003 ◽  
Vol 76 (4) ◽  
pp. 1001-1018 ◽  
Author(s):  
K. Naskar ◽  
J. W. M. Noordermeer

Abstract Thermoplastic vulcanizates (TPVs) or dynamic vulcanizates are thermoplastic elastomers produced by simultaneous mixing and crosslinking of a rubber and a thermoplastic. The effects of different types of peroxides as curing agents on the properties of PP/EPDM TPVs were investigated at a fixed blend ratio. The mechanical properties change significantly with the chemical nature of the peroxides, the extent of crosslinking of EPDM and the extent of degradation of PP. Three main parameters have been identified governing the final mechanical properties of TPVs: the solubility parameter of a peroxide relative to the substrates PP and EPDM, the fragmentation mechanism of the peroxide and the kinetic aspects of the peroxide fragmentation. Dicumyl peroxide gives the best balance of all properties, it complies the best of all with these parameters.

2017 ◽  
Vol 90 (1) ◽  
pp. 1-36 ◽  
Author(s):  
Shib Shankar Banerjee ◽  
Anil K. Bhowmick

ABSTRACT This article reviews different types of high-temperature thermoplastic elastomers and thermoplastic vulcanizates from rubber-plastic blends. Preparation, structure, and properties of these materials are discussed briefly. Strategies to further improve the high-temperature performance of these materials are presented herein. A synopsis of the applications of these high-performance materials in the automotive industry is reported, pointing out the gaps to motivate potential research in this field.


2004 ◽  
Vol 77 (5) ◽  
pp. 955-971 ◽  
Author(s):  
Kinsuk Naskar ◽  
Jacques W. M. Noordermeer

Abstract Thermoplastic vulcanizates (TPVs) or dynamic vulcanizates are a special class of thermoplastic elastomers, produced by mixing and crosslinking of a rubber and a thermoplastic polymer simultaneously. In a previous study, it was demonstrated that the use of dicumyl peroxide in combination with triallyl cyanurate as crosslinking agents provides a good overall balance of physical properties of PP/EPDM TPVs. Commonly used peroxides like dicumyl peroxide generally produce volatile decomposition products, which sometimes provide a typical smell or show a blooming effect. In this paper multifunctional peroxides are described, which reduce the above-mentioned problems. They consist of a peroxide and co-agent-functionality combined in a single molecule. The multifunctional peroxides provide properties of TPVs, which are comparable with commonly employed co-agent assisted peroxides. The solubility and kinetic aspects of the various peroxides are highlighted, as well as the decomposition products of the multifunctional peroxides with respect to the avoidance of smelly by-products. Particularly, 2,4-diallyoxy-6-tert-butylperoxy-1,3,5-triazine turns out to be a very good alternative to the dicumyl peroxide/triallyl cyanurate combination.


2011 ◽  
Vol 45 (11) ◽  
pp. 1189-1200 ◽  
Author(s):  
J. Cañavate ◽  
P. Casas ◽  
X. Colom ◽  
F. Nogués

Thermoplastic vulcanizates (TPVs) are a specific group of the so called thermoplastic elastomers. The main characteristic is the existence of a crosslinked rubber phase obtained by dynamic vulcanization in the presence of the thermoplastic matrix. This article studies TPVs based on ground tyre rubber (GTR), high-density polyethylene, and ethylene propylene diene monomer rubber. Vulcanization is performed by a new peroxide developed to resist high temperatures and an standard one. The aim of this study is optimize the formulation in order to include GTR, while maintaining a good balance of properties in the final TPV material. The use of GTR would improve the possibilities of recovering tyre waste. A detailed study regarding the influence of each component in the final mechanical properties has been carried out. The swelling properties, ATR infrared spectroscopy, TGA, and DSC analysis indicated a high degree of crosslink and good adhesion between the matrix and the rubber phase. Morphology of the composites was assessed by scanning electron microscopy. A composite containing a combination of peroxides and 40/30/30 of HDPE, EPDM, and GTR was found to show a good balance of characteristics regarding mechanical properties, crosslinking, and adhesion between phases.


2007 ◽  
Vol 80 (3) ◽  
pp. 504-519 ◽  
Author(s):  
Kinsuk Naskar

Abstract This review article introduces various aspects of dynamic vulcanization as applied to thermoplastic elastomers (TPEs). The classification of polymer blends and TPEs, the development of thermoplastic vulcanizates (TPVs), and the application of different types of crosslinking systems with special emphasis on peroxides/co-agents, and phenolic resins as crosslinking agents for polypropylene / ethylene propylene diene rubber (PP/EPDM) blends are primarily reviewed. The morphology and rheology of these TPVs are also touched upon.


2021 ◽  
Vol 13 (4) ◽  
pp. 2407
Author(s):  
Guang-Zhu Zhang ◽  
Xiao-Yong Wang ◽  
Tae-Wan Kim ◽  
Jong-Yeon Lim ◽  
Yi Han

This study shows the effect of different types of internal curing liquid on the properties of alkali-activated slag (AAS) mortar. NaOH solution and deionized water were used as the liquid internal curing agents and zeolite sand was the internal curing agent that replaced the standard sand at 15% and 30%, respectively. Experiments on the mechanical properties, hydration kinetics, autogenous shrinkage (AS), internal temperature, internal relative humidity, surface electrical resistivity, ultrasonic pulse velocity (UPV), and setting time were performed. The conclusions are as follows: (1) the setting times of AAS mortars with internal curing by water were longer than those of internal curing by NaOH solution. (2) NaOH solution more effectively reduces the AS of AAS mortars than water when used as an internal curing liquid. (3) The cumulative heat of the AAS mortar when using water for internal curing is substantially reduced compared to the control group. (4) For the AAS mortars with NaOH solution as an internal curing liquid, compared with the control specimen, the compressive strength results are increased. However, a decrease in compressive strength values occurs when water is used as an internal curing liquid in the AAS mortar. (5) The UPV decreases as the content of zeolite sand that replaces the standard sand increases. (6) When internal curing is carried out with water as the internal curing liquid, the surface resistivity values of the AAS mortar are higher than when the alkali solution is used as the internal curing liquid. To sum up, both NaOH and deionized water are effective as internal curing liquids, but the NaOH solution shows a better performance in terms of reducing shrinkage and improving mechanical properties than deionized water.


Life ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 43
Author(s):  
Lamya Zahir ◽  
Takumitsu Kida ◽  
Ryo Tanaka ◽  
Yuushou Nakayama ◽  
Takeshi Shiono ◽  
...  

An innovative type of biodegradable thermoplastic elastomers with improved mechanical properties from very common and potentially renewable sources, poly(L-lactide)-b-poly(2-methyl-1,3-propylene glutarate)-b-poly(L-lactide) (PLA-b-PMPG-b-PLA)s, has been developed for the first time. PLA-b-PMPG-b-PLAs were synthesized by polycondensation of 2-methyl-1,3-propanediol and glutaric acid and successive ring-opening polymerization of L-lactide, where PMPG is an amorphous central block with low glass transition temperature and PLA is hard semicrystalline terminal blocks. The copolymers showed glass transition temperature at lower than −40 °C and melting temperature at 130–152 °C. The tensile tests of these copolymers were also performed to evaluate their mechanical properties. The degradation of the copolymers and PMPG by enzymes proteinase K and lipase PS were investigated. Microbial biodegradation in seawater was also performed at 27 °C. The triblock copolymers and PMPG homopolymer were found to show 9–15% biodegradation within 28 days, representing their relatively high biodegradability in seawater. The macromolecular structure of the triblock copolymers of PLA and PMPG can be controlled to tune their mechanical and biodegradation properties, demonstrating their potential use in various applications.


Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 354
Author(s):  
Tim Tofan ◽  
Rimantas Stonkus ◽  
Raimondas Jasevičius

The aim of this research is to investigate related effect of dyeability to linen textiles related to different printing parameters. The study investigated the change in color characteristics when printing on linen fabrics with an inkjet MIMAKI Tx400-1800D printer with pigmented TP 250 inks. The dependence of color reproduction on linen fabrics on the number of print head passes, number of ink layers to be coated, linen fabric density, and different types of linen fabric was investigated. All this affects the quality of print and its mechanical properties. The change in color characteristics on different types of linen fabrics was determined experimentally. We determine at which print settings the most accurate color reproduction can be achieved on different linen fabrics. The difference between the highest and the lowest possible number of head passages was investigated. The possibilities of reproducing different linen fabric colors were determined.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 773
Author(s):  
Ahmad Safwan Ismail ◽  
Mohammad Jawaid ◽  
Norul Hisham Hamid ◽  
Ridwan Yahaya ◽  
Azman Hassan

Polymer blends is a well-established and suitable method to produced new polymeric materials as compared to synthesis of a new polymer. The combination of two different types of polymers will produce a new and unique material, which has the attribute of both polymers. The aim of this work is to analyze mechanical and morphological properties of bio-phenolic/epoxy polymer blends to find the best formulation for future study. Bio-phenolic/epoxy polymer blends were fabricated using the hand lay-up method at different loading of bio-phenolic (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) in the epoxy matrix whereas neat bio-phenolic and epoxy samples were also fabricated for comparison. Results indicated that mechanical properties were improved for bio-phenolic/epoxy polymer blends compared to neat epoxy and phenolic. In addition, there is no sign of phase separation in polymer blends. The highest tensile, flexural, and impact strength was shown by P-20(biophenolic-20 wt% and Epoxy-80 wt%) whereas P-25 (biophenolic-25 wt% and Epoxy-75 wt%) has the highest tensile and flexural modulus. Based on the finding, it is concluded that P-20 shows better overall mechanical properties among the polymer blends. Based on this finding, the bio-phenolic/epoxy blend with 20 wt% will be used for further study on flax-reinforced bio-phenolic/epoxy polymer blends.


Sign in / Sign up

Export Citation Format

Share Document