No abstract

In this research, binary polymer blends are formed from epoxy, unsaturated polyester and polyurethane. The concentration were chosen with varying percentages of components, resulting in three groups; polyurethane / epoxy (PU/EP), epoxy/unsaturated polyester (EP/UPE) and polyurethane/unsaturated polyester (PU/UPE) blends. Hand lay-up technique was used to prepare the samples with 6 mm thickness prepared from simultaneous mixing of the two constituents in the required percentages. Thermal conductivity K for these blends was carried out by using Lee’s disk method at room temperature. The experimental results showed that an increment and/or decrement of thermal conductivity depend on type and blend concentration. Also the experimental results indicated that the thermal conductivity has the highest values of (K) (0.78 J/m2.k) at ratios (PU 10% / EP 90 %), (0.70 J/m2.k) at ratios (EP 50% / UPE 50%) and (0.50 J/m2.k) at ratios (PU 40% / UPE 60%) respectively. This increment of (K) implies that the penetration of molecules of both polymer components in the same direct then a good transfer of energy by the vibration and rotation of the chain molecules. Also the experimental results indicated that the thermal conductivity has the lowest value of (K) (0.52 J/m2.k) at ratios (PU 40% / EP 60%), (0. 0.53 J/m2.k) has obtained at ratios (EP 30% / UPE 70%) and (0. 0.31 J/m2.k) has obtained at ratios (PU 60% / UPE 40%) respectively.

The goal is to study the effect of the SiO2 micro and nano-particles addition on the strength of epoxy composite based on glass fibers using (2, 4, 6 and 8) wt% of SiO2, the interlaminar fracture toughness (GIC) of 16-plies [M]16 of woven roving glass fiber /epoxy composites prepared by hand lay-up technique were investigated, using DCB test (mode I). The results computed using area method shows that the Interlaminar fracture toughness was increase with the filler content, higher values of GIC were observed for nano SiO2 composites as compared to microcomposites, because nano SiO2 behave as a barrier for crack propagation and the large surface density of these nanoparticles take a position in the polymeric chain restricting the movement for these chains leading to higher values of GIC in comparison with micro SiO2. The lower value of GIC found in 6 and 8 wt% is lower because, of the agglomeration of nano particles. This reflects the behavior of laminated nanocomposites into the same as microcomposites.

In this study, composite materials were prepared using unsaturated polyester resin as binder with two types of fillers (sawdust and chopped reeds). The molding method is used to prepare sheets of UPE / sawdust composite and UPE / chopped reeds composite. The mechanical properties were studied including flexural strength and Young's modulus for the samples at normal conditions (N.C). The Commercial wood, UPE and its composite samples were immersed in water for about 30 days to find the weight gain (Mt%) of water for the samples, also to find the effect of water on their flexural strength and Young's modulus. The results showed that the samples of UPE / chopped reeds composite gained highest values of flexural strength (24.5 MPa) and Young's modulus (5.1 GPa) as compared with other composites at (N.C). The results showed that the wet samples of sawdust composite have lowest values of weight gain (Mt %) of water (0.043%) as compared with other composites after immersion. Also it’s showed a slight decrease in values of Young's modulus for all the samples after immersion as compared with the samples at (N.C). Finally it’s showed a slight decrease in values of flexural strength for all the samples except for the composite material formed from UPE / chopped reeds which showed an increase in the value of flexural strength after immersion, where the wet samples of UPE / chopped reeds composite gained (29 MPa) as compared with the samples at (N.C).

This work focuson study thermal conductivity for polymers and their nanocomposites usingtoner carbonnano-particles(TCNP)with particles sizeof (89.77nm) asanano-particles, with different weight percentages(2, 4 and6) % to unsaturated polyester (UPE) and epoxy (EP) resins as a matrix to prepare nano-compsites. Molding method was used to prepare polymers and their nano-composites sheets.The results show (UPE) has highest value than(EP). Adding nano-particle to (UPE) and (EP) will increase thermal conductivity for nano-composites. The values of thermal conductivity for two types of resins UPE and EP without any additions are (0.181W/m. o c and 0.154W/m. o c) respectively. At the weight fraction(2%) the value for (UPE/TCNP) samples is (0.355W/m. o c),while the value for EP/TCNP samples is (0.405W/m. o c), and the values of the thermal conductivity begin increasing with the increasing ofthe weight fraction which used in this research, were the highest value for (EP/TCNP) samples is (0.429W/m. o c)at weight fraction(6%).