An Investigation and Characterization of Monkeypod Tree Flower Particulates Filled PLA Composites

Samanea saman (SS) ower particulates were lled in Polylactic acid (PLA) composites were fabricated with different 0, 10, and 20 wt. % through the injection molding process. The elemental composition and morphology of SS PLA composites were studied through FESEM and Energy Dispersive X-ray analysis. Thermal stability of the SS PLA composites specimens was carried out through Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimeter (DSC). Crystal orientations studied through X-Ray Diffraction (XRD) showed the presence of the orthorhombic SS particulates. The properties of the composites were investigated such as tensile strength, compressive strength, exural strength, and Shore D Hardness. It was found that 20 wt. % of SS lled PLA composites has a superior tensile strength of 43.76 MPa, the compression strength of 37.94 MPa, the exural strength of 72.47 MPa, and Shore D Hardness of 80.1 SHN than pure PLA. SS particulates-lled PLA composites would be used for low-strength applications.


Introduction
The natural bers lled composites were used in cosmetics, packaging, medical applications, and agriculture. PLA and bers composites showed good processability through injection molding for 20-30% ber content (Cinelli et. al 2021). PLA has been used for biodegradable products, such as planting cups, and plastic bags. The stiffness of the PLA composites was increased from 3.4 to 8. 4 GPa with the incorporation of 30 wt. % ax bers (Oksman et. al 2003). PLA composites were developed through reinforcing nanoparticles such as graphite, silica, inorganic metal, and metallic oxides exhibited improvement of the glass transition temperature, crystallinity, modulus, tensile strength, and antimicrobial property (Mulla et. al 2021).
The coconut shell powders blended in PLA composites decreased the tensile strength and the surface modi cation of ller using acrylic acid improved the modulus of elasticity, thermal stability, and tensile strength, of PLA/CSP biocomposites (Salma et. al 2013). The tensile modulus of unidirectional composites was signi cantly higher than that of the PLA (i.e., ~40%). Since the unidirectional composites were revealed tensile strength slightly higher than that of the neat matrix (Botta et. al 2015). 30% wt., HAp-HDPE contributed to the slight toxicity of the composite after interacting with the MG63 cell line.
Such an extracted HAp would be useful as inexpensive ceramics are environmentally and biologically compatible materials (Balaji Ayyanar et. al 2020).
The 30 wt. % of cotton gin waste was incorporated in PLA composites was revealed a 42% increment in exural modulus as compared with neat PLA (Bajracharya et. al 2017). The mechanical properties and microhardness of PLA composites were increased due to the high rigidity of calcined seashell inorganic bio-ller (Razali et. al 2021). Mussel shells lled PLA biocomposites revealed excellent mechanical properties, without signi cantly lowering the composite strength and improving the elastic modulus (Gigante et. al 2020). The direction ber content in the composites was signi cantly increased moduli between 70% up to 6 times greater than the matrix. Young's modulus and highest tensile strength were found in PLA self-reinforced composite than PBS composites (Jia et. al 2014). The PLA composites revealed higher deformation at break higher than 120% also when 20 wt. % of ller was lled in the composite. Differential Scanning Calorimetry analysis of the PLA composites revealed that microcrystalline cellulose llers mostly affect the crystallinity of polybutylene adipate-co-terephthalate (Botta et. al 2021).
The modi cation of the properties of both PLA and ax bers may also lead to an increase in energy absorption, impact strength, and thermal stability of the composites (Sanivada et  shows the SS llers, PLA, and SS PLA composites specimen.

Fabrication of the Composites
To develop the composites specimens, a systemic approach was carried out. The methodology and process that was carried out to develop a SS particulate-lled PLA composite specimen as shown in Figure. 2 SS owers were collected from the trees growing in and around our college campus. The stem of the owers was cut down and only the head was used. The owers were cleaned again and again with cold water to remove the impurities.
The cleaned owers were dried to room temperature for 8-10 days until they dried completely. The 1 kg of dried owers were grinded into powder at the speed of 1500 rpm through the oor mill. To fabricate the composites specimen mixtures of the required quantity 0, 10, and 20 wt. % SS particulates lled in PLA. Each weight percentage of mixtures was preheated at 100°C for about 10 min and introduced in the heating chamber for further heating. The temperature 110±5 ℃ was preferred in injection molding to control the melting of the matrix.
The manual operating pressure was adjusted to 60 -65 bar during the injection process. PLA pellets and SS powder particulates were fed into the hopper. Once the material passes through the hopper it enters the injection barrel. The barrel consists of separately controlled heating zones. The semi-melted mixtures were injected into mold cavities in the die as per ASTM standards and removed immediately. By increasing the SS particulates by more than 20 wt. % in PLA leads to the burning of SS llers during the molding process. Due to these limitations, the llers were incorporated upto 20 wt. % in PLA which was affected the quality of composites.
3. Characterization Techniques i) XRD ii) Surface morphology and EDX analysis of SS particulates lled PLA composite were examined using a ZEISS Sigma 300 Scanning Electron Microscope iii) DSC analysis was carried out under owing nitrogen (Nitrogen 50 ml/min). The sample with a mass of 9 mg was heated gradually from 10° C to 500°C at a rate of 20° C/ min and found the peak melting temperatures and thermal energy required for phase changes of the 20 wt. % SS PLA Composites. iv) Thermogravimetric Analysis (TGA) was carried out using a Q600 SDT (TA Instruments, USA) with a mass of 9 mg was heated gradually from the temperature of 50° C to 600° C at a constant heating rate of 20°C/min under owing nitrogen (20 mL/ min).

X-Ray Diffraction Analysis
X-ray diffraction analysis (XRD) is a technique used in materials science to determine the crystallographic structure of a material. The locations (angles) and intensities of the diffracted X-rays are measured and given in Table.1. The XRD test results show a peak value between 10 to 25 degrees as shown in Figure 3. It con rmed the presence of AlPO-8 in SS Powder. The crystal structure was found to be in orthorhombic structure. Compound Name: AlPO-8, Chemical Formula: Al1 O4 P1, Mineral name: Berlinite, Crystal Structure: Orthorhombic is given in Table.2   Table 3.  Figure. 6 shows a negative peak which means that the 20 wt. % SS PLA Composites absorbs energy due to an endothermic reaction. The peak melting temperature was found to be 312.4°C and at this transition, the material changed from being relatively hard to a rubbery material. The energy absorbed by the powder at peak temperature was found to be -196.8J/g. Up to 280±5° C the weight of 20 wt. % SS PLA composites was stable and there was no change in mass in that range of temperature. When the temperature was increased beyond 280°C to 300°C huge quantity of weight was decreased. On further increasing the temperature from 300°C to 547.9°C remaining 20 wt. % SS PLA composites had been decomposed and exhausted. During this most functional presence in the composites was decomposed. The residual mass was found to be 12.23%.

Mechanical Characterisation of the Composites
The tensile strength of PLA 37±0.5 MPa was found and it was gradually increasing by varying the particulate from 0, 10, and 20 wt. % respectively. The tensile strength was gradually increased by increasing the SS particulates contents in PLA composites which were observed in the test.   Table. 3

Conclusion
The structural and elemental compositions of SS particulates were studied using XRD and EDX analysis. The surface morphology was studied through FESEM. SS PLA composites specimens were characterized the thermal stability using TGA and DSC. The peak melting temperature was found to be 312.4°C and at this transition, the material changed from being relatively hard to a rubbery material. The energy absorbed by the SS PLA composites at peak temperature was found to be -196.8J/g. When the temperature is increased beyond 280°C to 300°C huge quantity of weight had decreased. On further increasing the temperature from 300°C to 547.9°C remaining 20 wt. % SS PLA composites had been exhausted. Compared to pure PLA composites the 20 wt. % SS PLA composites revealed the tensile strength of more than 15% of pure PLA The exural strength was increased from 0 to 20 wt. % SS particulates lled HDPE composites after that is started decreasing strength. The maximum hardness of the 20 wt. % SS PLA composites were increased 4. 5% compared with pure PLA.