PREPARATION OF POLYMERIC COMPOSITES FROM SATURATED POLYESTERS GLASS POWDER (FLOURSCENT) AND STUDY OF ITS MECHANICAL PROPERTIES

In this study, polymeric composites were prepared from unsaturated polyester as a base material with glass powder (fluorescent) in different weight ratios (4, 6, 8, 10,and 11%) as a support material and after comparison before and after reinforcement of the prepared composites, an increase was found. In the values of mechanical properties (hardness, compressive strength), the shock resistance values decreased, but an increase in temperature leads to an increase in the values of shock resistance, as well as the values of compressive strength And it reduces the hardness value.


INTRODUCTION
Composite materials possess some properties that are suitable for a number of industrial applications, so they have gained an important position among the engineering materials (Ives et al., 1971). Composite materials generally are formed by combining two or more materials to obtain a material with engineering and physical properties that has better properties than the materials included in its composition. The composite material consists of three phases; the matrix phase and the Reinforcing phase the intermediate phase between them (the interphase) (Akovali, 2001). The interest in polymer-based composites increased due to their engineering capacities, especially in applications that requires high-quality resistance. The most important materials that are used as basic materials are the three types of polymeric materials that are thermoplastics, thermosetting and elastomers (Al Adam 1983; Mouzakis, 2008). Plastic composite materials reinforced with different types of supporting materials include two types of base materials, which are a thermoplastic base material and a thermo set base material. It should be noted that thermostats are stronger than thermoplastic materials which are widely used such today such as low-density polyethylene, high-density polyethylene, and polypropylene (Akovali, 2001). Unsaturated polyester resin is a thermally hardening resin and cannot be used alone in engineering applications, because it is a brittle material and does not have the appropriate efficiency, however ,it can be strengthened with some strengthening materials such as glass fiber, carbon fiber, and glass waste powder particles affect some of the mechanical properties of the brittle unsaturated polyester. They also affect the fracture toughness. (Varga, et al., 2010). Waste glass powders are a non-metallic and inorganic substance. This material is not burnt and does not decompose, so it is difficult to recover (Malik, 2000). Among the applications of these materials in corrosive media is their use in chemical industries such as tanks, pipelines, cleaning devices, because of their resistance to corrosive acid media such as (H 2 SO 4 ) used in space and the automobile industries (Callister, 2005). The aim of the study: This study aims to prepare composite materials that show good resistance to shocks and high compressive strength, identify the behavior of polymeric materials under standard conditions, make a comparison between them and the polymeric material before reinforcement, and then study the mechanical properties (impact strength, hardness, compressive strength) for all samples before and after the reinforcement with fluorescent glass powder.

MATERIALS AND METHODS The matrix
The unsaturated polyester made by (B-CHEM SRL) company was used as the matrix, which is in the form of yellowish glue at room temperature, it is a type of Thermosetting polymers, that turns from the semi-solid state to the solid state by the addition of the hardener (di benzoyl peroxide), which is at the form of white cream that is added to the unsaturated polyester resin in a ratio of 2:1 at room temperature (Mark, 1999). Waste glass powder was also used in the form of powder, the powder was obtained after grinding and sifting by a 200mesh sieve in the laboratory to obtain the granular size 75μm. Suitable samples could be obtained for molding at room temperature.

Reinforcing materials
Reinforcing materials (Glass Powder that was sifted with a 200-mesh sieve) were used to reinforce the unsaturated polyester resin. The (damaged glass of candles) of the type (PARS LAMP 18W) from Iran was used.

Preparation of samples
Three types of samples were prepared for the mechanical tests: Impact test samples: Impact test samples were prepared according to American standard (256-87ASTM-D) with dimensions (10×55mm×10 3 ) for the examination. The grooving depth in the models is (2mm) with a notch angle of (45°). The absorbed energy required for the occurrence of the breakage was obtained directly from the Charpy Impact Instrument provided by (Tokyo Koki Seizosho, LTD) (Figure 1), Illustrates the shape and dimensions of the sample prepared for the impact strength testing (Al-Bakri, 2012).

Hardness testing samples
Non-standard models were used. Any model of composite material would be suitable for this test. The hardening device of the (Rockwell) hardness type was used, the penetration tool is a hardened steel ball with a diameter of (12.7mm) for the weight applied (60kg), equipped from the company (WOLPERT-Germany) for measuring the hardness of thermosetting polymer. The method of examination is to place the device perpendicular to the sample for which the hardness is to be measured in order for the needle to be inserted into the surface of the material and then wait for a period of three seconds after which the hardness value is taken from the device, and no less than three readings were taken from different places of the sample and then the average was taken (Al-Mosawi, 2009).

Samples of compressive resistance test:
The compressive resistance test models were prepared according to the specification (618ASTM-D) it is a cylindrical device using a hydraulic press of the type (Testing Machine Co.LTD) supplied by (WOLPERT -Germany) to determine the maximum compressive load the sample can bear, and by dividing the load by the cross-sectional area of the model before the deformation  (Figure 2) shows the shape of the sample prepared for compressive resistance testing.

Figure (2):
The shape of the sample prepared for compressive resistance testing.

Preparation method
An unsaturated polyester resin was used with a hardener (di benzoyl peroxide) in a ratio of 2:1 to turn it into a solid material that solidifies at room temperature. Then samples were prepared of composite materials of unsaturated polyester reinforced with glass powder with weight ratios of (4, 6, 8, 10,and 11%). Hand-Layup Molding was followed in the process of preparing samples before and after using the powder in reinforcement (Sulyman et al., 2019).
The resin was prepared by adding a hardener to the unsaturated polyester in a ratio of (1:2), then the resin was added to the hardeners, and then the mixture was placed in the molds designated for measurements, which were made according to the standard specifications for each examination, and after the completion of the pouring process, it was left for 24 hours at a temperature of (23°C) and (53°C) to complete the curing process, overlap, homogeneity between the particles, and reduce the internal stresses formed during the pouring process, (Figure 3) shows a schematic diagram of the templates used in preparing samples.

RESULTS AND DISCUSSION Impact strength
Examination of impact strength is one of the practical methods that give a correct indication of materials strength and resistance to fracture under stress at high velocity (Alrawi & AlHalim, 2019). The impact strength is calculated using the equation: (Figure 4) we notice that the impact strength decreases with the increase in the percentage of addition of damaged candle glass powder, this is an expected result because the glass is a brittle ceramic material, (Figure 5) shows the effect of the weight ratios of the unsaturated polyester support material on the impact resistance of polymeric composites at the processing temperature (23-53°C), (Table 1) shows the effect of the weight ratios of the reinforcement material added to the unsaturated polyester on the impact resistance of polymeric composites at the processing temperature (23-53°C).

HARDNESS
The hardness property is one of the most important mechanical properties of the material, it's considered as a measurement of plastic deformation, in which the material suffer from an influence of an external stress, imposed on it by its exposure to scratching and penetration with tools that are stiffer than it during its use in various applications (Anothony & David, 1983), through research It was found that the higher the percentage of addition of damaged candle glass powder, the higher the hardness value. The reason behind that is that the glass is a ceramic material that gives hardness to the base material (polyester). As a result of the physical contact between the glass particles and the polymeric chains, the penetration resistance of the composite material is decreased. (Figure 6 and 7) shows the effect of the weight ratios of the support material added to the unsaturated polyester on the hardness value of polymeric composites at the processing temperature (23-53°C), ( Table 2) hardness values of unsaturated polyesters before and after the reinforcement with deferent weight ratios the temperature varies between 23 and 53°C.

Compressive resistance test
It is one of the most important tests to know the durability and strength of the polymer. There are number of materials that may be brittle in tension condition, but appear ductile in compression. Therefore, compressive resistance testing is used to determine the submissive strength as well as the compressive strength (Sulyman et al., 2019). It is defined as the amount of mechanical stress that a solid material endures under perpendicular stress. Without breaking or shattering or changing in its shape after the stress is removed. This test is widely used to examine fragile materials such as glass, concrete pieces, rocks, mastic iron and heat-hardened polymers due to the fact that these materials have more strength in compression than in tension condition, test samples used are cubic or cylindrical (Sulyman & Sulyman, 2020), (Figure 9 and 8) shows the effect of the weight ratios of the support material added to the unsaturated polyester on the value of the compressive strength of polymeric composites at the processing temperature (23-53°C), ( Table 3) Compression strength of unsaturated polyester before and after reinforcing in different proportion weights at 23 and 53°C.