Pultruded fibre-reinforced polyurethane composites. III. Static mechanical, thermal, and dynamic mechanical properties

ABSTRACT The influence of the structure and size of carbon black on the static mechanical and dynamic mechanical properties of filled natural rubber (NR) compounds is investigated in detail. A new process for the production of carbon black master batches with enhanced mechanical properties has been developed. The unit operations in the process are the preparation of carbon black slurry in the presence of a suitable surfactant, addition of the slurry to the fresh NR latex under stirring, coagulation of the mixture by the addition of acid, dewatering of the coagulum, and drying to obtain carbon black–incorporated NR. The competence of the new technique is established by comparing the characteristics of the carbon black–incorporated NR by the mill mixing process (control). The mechanical properties, including tensile strength, modulus, tear strength, and hardness, are superior for the vulcanization prepared by the latex-suspension coagulation techniques. The improvement shown by the vulcanization prepared by the latex-suspension coagulation techniques was attributed to the better filler dispersion evidenced from the scanning electron micrograph along with the attainment of a higher level of vulcanization.

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Study on Cyclic Compressive and Dynamic Mechanical Properties of Porous Polyurethane Composites Prepared with Hollow Silica Microspheres

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19422 ◽

2021 ◽

Vol 21 (8) ◽

pp. 4438-4443

Author(s):

Bomin Kwak ◽

Younghwan Kwon

Keyword(s):

Mechanical Properties ◽

Superposition Principle ◽

Dynamic Mechanical Properties ◽

Bulk Polymerization ◽

Silica Microspheres ◽

Hollow Silica ◽

Dynamic Mechanical ◽

One Step ◽

Time Temperature Superposition Principle ◽

Polyurethane Composites

Porous polycaprolactone-based polyurethane composites containing hollow silica microspheres were synthesized by one-step bulk polymerization. The effects of incorporated hollow silica microspheres on the cyclic compressive and dynamic mechanical properties of the composites were examined. Cyclic compression testing was carried out to record the accumulated stress versus strain profiles during 100 continuous loading and unloading cycles and to study the compressive behavior and time-dependent recovery of the composites. The effects of frequency on the dynamic mechanical properties of the composites was also investigated using a dynamic mechanical analyzer. Cole–Cole and Wicket plots were drawn to check the validity of the time-temperature supposition of the composites in the temperature and frequency ranges considered. Master curves of the composites were constructed based on the time-temperature superposition principle to obtain the long-term dynamic mechanical behavior of the composites.

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Effect of Sisal Fibre Hybridisation on Static and Dynamic Mechanical Properties of Corn/Sisal/Polylactide Composites

Polymers and Polymer Composites ◽

10.1177/096739111702500605 ◽

2017 ◽

Vol 25 (6) ◽

pp. 463-470 ◽

Cited By ~ 2

Author(s):

Honglin Luo ◽

Dehui Ji ◽

Guangyao Xiong ◽

Lingling Xiong ◽

Chuanyin Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Hybrid Composites ◽

Dynamic Mechanical Properties ◽

Peak Height ◽

Sisal Fibre ◽

Dynamic Mechanical ◽

Static Mechanical ◽

Tan Δ ◽

First Time ◽

Static Mechanical Properties

The relatively poor mechanical properties of corn fibre (CF) and its green composites have hindered its applications. In this work, sisal fibre (SF) was hybridised with CF to reinforce polylactide (PLA) composites (CF/SF/PLA). The static mechanical properties such as tensile, flexural and impact strengths and dynamic mechanical properties such as storage modulus (E’), damping behaviour (tan δ), glass transition temperature (Tg) of the hybrid composites were determined and, for the first time, hybrid effects on both static and dynamic mechanical properties were evaluated. It is found that the tensile, flexural, impact strengths, and E’ and tan δ peak height, as well as the hybrid effects change with hybrid ratio (SF:CF). It is demonstrated that a hybrid composite with desirable static and dynamic mechanical properties can be produced by optimising the fibre:hybrid ratio.

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Static and dynamic mechanical behavior of doum palm (Hyphaene thebaica) nut reinforced HDPE composites

Nigerian Journal of Technology ◽

10.4314/njt.v40i4.11 ◽

2021 ◽

Vol 40 (4) ◽

pp. 639-647

Author(s):

A.A. Alabi ◽

A.I. Obi ◽

D.M. Kulla ◽

S.M. Tahir

Keyword(s):

Mechanical Properties ◽

Dynamic Mechanical Properties ◽

Particle Sizes ◽

Load Bearing Capacity ◽

Palm Fruit ◽

Environmental Friendliness ◽

Dynamic Mechanical ◽

Dynamic Mechanical Behavior ◽

Static Mechanical ◽

Static Mechanical Properties

The quest to discover more and to enhance the qualities of agro-residue for use as natural reinforcement of polymers continues to attract the attention of researchers because of the environmental friendliness. Hyphaene thebaica also known as doum palm is a fruit tree native to the Nile in Egypt and found in abundance in many parts of Africa. Doum palm fruit contains probably the hardest and toughest known nut. The doum palm nuts (DPN) are the most under-used hard-nut despite their abundance in nature. This study presents the potential doum palm nut particles (DPNp) as natural reinforcement for high density polyethylene (HDPE). Properties of DPN such as density, hardness and weight loss due to heating were determined. HDPE/DPNp composites were produced by reinforcing HDPE with 30, 35, 40 and 45% DPNp particles of two different sizes. The particle sizes 600 μm and 710 μm led to classifying the composites as X-composite and Y-composite respectively. The static and dynamic mechanical properties of the composites were determined and compared with the those of pure HDPE. Results showed that HDPE and DPNp can be formed into light and attractive components. Loading HPDE with DPNp significantly improve static mechanical properties of HDPE such as tensile strength, hardness, stiffness and resistance to impact failure by 50%, 200%, 800% and 1500% respectively. The HDPE/DPNp composites also had better dynamic mechanical properties. The ability of the composites to maintain load bearing capacity under dynamic conditions was superior to that of HDPE.

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Effect of Hollow Silica Microspheres on Compressive and Dynamic Mechanical Properties of Hydroxyl-Terminated Polybutadiene-Based Polyurethane Composites

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19183 ◽

2021 ◽

Vol 21 (7) ◽

pp. 3813-3818

Author(s):

Bo Min Kwak ◽

Younghwan Kwon

Keyword(s):

Mechanical Properties ◽

Superposition Principle ◽

Dynamic Mechanical Properties ◽

Mechanical Analysis ◽

Bulk Polymerization ◽

Silica Microspheres ◽

Hollow Silica ◽

Dynamic Mechanical ◽

Time Temperature Superposition Principle ◽

Polyurethane Composites

Porous polyurethane composites containing hollow silica microspheres were prepared by one-step bulk polymerization to study cyclic compressive and dynamic mechanical properties of the composites. Cyclic compression testing was conducted to record the stress versus strain curves during the loading and unloading cycles and in order to study the compressive behavior and time-dependent recovery of the composites. Effect of frequency on the dynamic mechanical properties of the composites was also evaluated using dynamic mechanical analysis. Master curves were constructed based on time-temperature superposition principle in order to show long-term dynamic mechanical behavior of the composites.

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