The Effect of Treatment of Coconut Fiber with Liquid Smoke on Mechanical Properties of Composite

This study aims to determine the effect of liquid smoke treatment on the tensile strength of the single fiber and Coconut fiber (CF) Reinforced Composite. The research method is Immersion the fiber with liquid smoke and heating. First treatment, CF was immersed in liquid smoke for 1, 2, and 3 hours, then dried for 1 hour at a temperature of 40 degrees Celsius. Next, the single fiber tensile test was carried out with the Universal Impact Test Machine and composite impact strength. The results showed that the tensile strength of single fiber TP, P1J, P2J, and P3J of 51.357 MPa, 79.655 MPa, 48.187 MPa, and 58.117 MPa. While the CF composite impact test TP, P1J, P2J, and P3J of 0.514 KJ/m2, 1.385 KJ/m2, 1,085 KJ/m2, and 2,128 KJ/m2. The liquid smoke immersion can increase the tensile strength of single fibers, where 1-hour immersion has the greatest value. In contrast, the impact strength of the CF composites increased at 3 hours, the largest immersion value. The results showed that the fiber soaked in liquid smoke could be an alternative to improve the mechanical properties of CF.


Introduction
The development of research that utilizes renewable and biodegradable materials to replace metal materials is very rapid [1] [2][3] [4]. Researchers are currently focusing on non-metallic materials from fibrous plants because the fiber can be used as a composite reinforcement and is easy to obtain, inexpensive, and has mechanical properties [5] [6], such as sago sheath fiber [6], bamboo fiber [7]., pineapple fiber [8], and palm fiber [9] North Maluku, as one of the eastern provinces of Indonesia, is one area that has the potential to research natural fibers into composite reinforcement materials, where there are several studies on natural fibers that have been carried out in eastern Indonesia, including sago fiber, king pineapple fiber, fiber fibers, and others [10] [9].
In the series of studies mentioned above, treatments were carried out to improve micro and macro properties, including physical properties and mechanical properties, as for some of the treatments carried out by soaking the fibers with chemical liquids such as treatment with alkali [11][12] [13] and non-chemicals such as turmeric liquid [14], liquid smoke [10], and fumigation [8]. The potential of using Coconut Fiber (CF) originated from the island of Ternate, North Maluku, eastern Indonesia, as a composite reinforcement. The fiber is the outermost part of the coconut fruit. The coconut belt consists of an outermost layer (exocarpium) and an inner * Corresponding author : mukhlis@yahoo.com layer (endocarpium). Endocarpium contains fine fibers that can be used as composite reinforcement [15].
The treatment material uses liquid smoke, which results from the pyrolysis process of natural ingredients such as coconut shell, which has the same content as fiber consisting of lignin, hemicellulose, and cellulose [2]. Liquid smoke can change the material texture [16] and the texture of natural fibers [10]. Increase in tensile strength of single fiber on 1-hour liquid smoke immersion [6]. Liquid smoke can change the chemical and thermal properties of the fiber [17], and liquid smoke is also antimicrobial [18] [19], which can inhibit the potential for microbial growth on the fiber so that it inhibits fiber damage in its use.

Methodology
The material used is coconut coir fiber, which is taken from Ternate City, North Maluku Province. The research method was carried out by soaking the fiber in liquid smoke in a container with variations in immersion time of 1, 2, 3 hours, and without treatment. After that, it was dried in a dryer/oven at 40°C for 30 minutes. Then the fiber is cut to a length of 9 cm, and a test specimen is made with the addition of paper and glue. While in the Impact Test Specimen, the material used is YUKALAC 157 98% resin, 2% fiber with a fiber length of 4 cm, and a catalyst then mixed in a container and then poured into a composite mold until hardened and then made into

Impact Test Specimen
The impact test specimen uses the ASTM D256-02 standard. Impact testing is carried out by preparing test materials that have passed the specimen manufacturing process according to the ASTM D256-02 standard.
After the impact test, equipment is per the data taken. Then, install the specimen, operate the impact test equipment until the specimen breaks, record the test results, or save the test equipment readings.

Result and Discussion
The results showed the effect of coco fiber treatment on the tensile strength of single fiber and the impact strength of the composite with variations without immersion, immersion 1, 2 and 3 hours.   In the type of treatment variation and TP where the immersion of coconut coir fiber with liquid smoke increases the impact strength, the P1J shows an increase in the mechanical properties of the impact strength of 1.385 KJ/m² from that TP of 0.514. In comparison, the P2J experiences a decrease of 1,085 KJ/m² and an increase of 2.128 KJ/m² on immersion for P3J. Thus, the graph above shows that soaking coconut coir fiber with liquid smoke can increase the mechanical properties of the impact strength. This is due to an increase in the tensile strength of a single fiber so that the coconut belt fiber, when used as a composite reinforcement, will increase the impact strength. Figures 1 and 2 also show that the tensile strength of the coconut belt fiber is directly proportional to the impact strength of the coconut belt reinforced composite, where the tensile and impact strengths in P1J increase from the tensile and impact strengths without treatment. In addition, the increase and decrease in tensile and impact strength are the same where P2J decreases and in P3J treatment increases. However, in general, the treated coconut fibers experienced an increase in mechanical properties compared to those that were not treated.

Impact Test
Changes affect the increase in tensile and impact strength on the compound bond of coconut belt fibers with liquid smoke, where there is a carbon bond (CC) in the fiber [17], resulting in an increase in the strong, attractive force between the carbon elements.
Improving the mechanical properties of coconut belt fibers due to liquid smoke treatment is one solution in increasing the strength of coconut fibers so that they can be used as an option in the manufacture of coconut belt fiber-reinforced composites. Coconut fiber-reinforced composites are becoming a new choice in the manufacture of composite material products 4 Conclusion