The effect of variations in fibre length on the impact strength of poly(methyl methacrylate) resin reinforced with ultra-high-modulus polyethylene fibre

1993 ◽  
Vol 12 (3) ◽  
pp. 137-140 ◽  
Author(s):  
D.L. Gutteridge
2018 ◽  
Vol 773 ◽  
pp. 51-55
Author(s):  
Jasmine Pongkasem ◽  
Saowaroj Chuayjuljit ◽  
Phasawat Chaiwutthinan ◽  
Amnouy Larpkasemsuk ◽  
Anyaporn Boonmahitthisud

In this study, poly(lactic acid) (PLA) was melt mixed with three weight percentages (10–30wt%) of ethylene vinyl acetate copolymer (EVA) in an internal mixer, followed by a compression molding. According to a better combination of mechanical properties, the 90/10 (w/w) PLA/EVA was selected for preparing hybrid nanocomposites with three loadings (1, 3 and 5 parts per hundred of resin , phr) of poly(methyl methacrylate)-encapsulated nanosilica (PMMA-nSiO2). The nanolatex of PMMA-nSiO2 was synthesized via in situ differential microemulsion polymerization. The obtained PMMA-nSiO2 showed a core-shell morphology with nSiO2 as a core and PMMA as a shell, having an average diameter of 43.4nm. The influences of the EVA and PMMA-nSiO2 on the impact strength and the tensile properties of the PLA/EVA nanocomposites were studied and compared. It is found that the impact strength and the tensile properties of the 90/10 (w/w) PLA/EVA were improved with the appropriate amounts of the EVA and PMMA-nSiO2.


An optically transparent material with enhanced physical-mechanical properties was synthesized, which is based on the in situ formed sequential interpenetrating polymer networks of poly(methyl methacrylate)/polyurethane with an oligoester component. The kinetic features of polymerization of methyl methacrylate in these systems were studied. It was established that the polymerization rate of methyl methacrylate increases with an increase in the content of a polyurethane component, which results from an increase in the system viscosity. Irrespective of the content of polyurethane (15, 20 or 25 wt.%), optically transparent materials with a light transmission coefficient of about 90% were formed. The method of dynamic mechanical analysis showed that the modification of cross-linked poly(methyl methacrylate) with cross-linked polyurethane led to a decrease in the value of the elastic modulus; the value of the loss modulus being increased with an increase in polyurethane content. This indicated bot a decrease in fragility and the improvement in impact strength of the glass-like material. According to the study of physical-mechanical properties of the materials, the presence of polyurethane in their composition resulted in an increase in the impact strength and relative breaking elongation and in the reduction of the Young modulus. It was found that the interpenetrating polymer network containing 20% of polyurethane showed the best values of breaking strength, breaking elongation and Charpy impact.


2012 ◽  
Vol 32 (4-5) ◽  
pp. 275-282 ◽  
Author(s):  
Azman Hassan ◽  
Noor Izyan Syazana Mohd Yusoff ◽  
Aznizam Abu Bakar

Abstract The influence of talc and poly (methyl methacrylate) (PMMA)-grafted (g)-talc on the mechanical properties of poly (vinyl chloride) (PVC) was investigated. The graft copolymerization was carried out under nitrogen atmosphere, using the free radical initiation technique. The blend formulations were first dry blended using a mixer before being milled into sheets on a two-roll mill at 165°C, and then hot pressed into composites at 190°C. The flexural modulus of both composites increased with increasing filler content from 0 to 20 part per hundred resin (phr), however the increment of grafted (57.7%) was higher than ungrafted composites (48.5%). A similar trend has also been observed for thermal stability. The impact strength of grafted was increased by 45.82%, whereas 18.96% in reduction was observed for the ungrafted composites. The decrement of flexural strength by 16.6% and 21.1% of grafted and ungrafted, respectively, has also shown the improvement in mechanical properties of grafted composites.


2016 ◽  
Vol 124 (2) ◽  
pp. 709-717 ◽  
Author(s):  
Mahmoud A. Hussein ◽  
Reda M. El-Shishtawy ◽  
Bahaa M. Abu-Zied ◽  
Abdullah M. Asiri

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