# Effect of LNR-g-MMA on the Mechanical Properties and Lifetime Estimation of PLA/PP Blends
## 1 Introduction
[2] presented a melt blend of PLA/PP and PLA/PP with liquid natural rubber (LNR) compatibilizer in a ratio of 90:10 for PLA/PP and 90:10:10 for PLA/PP/LNR. They discovered that the elongation at break, flexural, and notched impact strength rose dramatically for the LNR\(-\)compatible PLA/PP blend. [PERSON]\(-\)[PERSON] et al. [11] produced a compatibilized terpolymer of ethylene, butyl acrylate, and glycidyl methacrylate, and non\(-\)compatibilized blends of PP and PLA with different nanoclay particle-containing compositions. According to their findings, adding more PLA to the blends increased their tensile modulus and strength while decreasing their elongation at break. The decrease in the size of the disperse phase and increase in the polydispersity of the droplet size in compatibilized PP/PLA blends, as compared to those for uncompatibilized blends, correspond to the effect of the terpolymer compatibilizer on the interfacial interaction between the phases, resulting in a smaller droplet size and a higher polydispersity. The relationship between immiscible PLA/PP blends of different compositions and the compatibilizer loading via melt mixing has been reported in a few studies. The effect of compatibilizer loading on the blends' properties was also investigated. However, the addition of more than 20-30% compatibilizer into PLA matrix can cause the phases between the polymer blend to separate [19]. [PERSON] et al. [20] prepared PLA/PP blends of different compositions with 0, 2.5, 5.0, 7.5, and 10.0 wt% EBA\(-\)GMA (ethylene-butyl acrylate\(-\)glycidyl methacrylate copolymer) used as a compatibilizer. They reported that the tensile strength of the PLA/PP (70:30 wt%) blends reached a maximum for 2.5 wt% EBA\(-\)GMA, and impact strength increased with increasing EBA\(-\)GMA content. [PERSON] and [PERSON] [21] studied the relationship between compatibilizer and yield strength of PLA/PP blends at 70:30, 50:50, and 30:70 ratios. In addition, PP\(-\)g\(-\)MAH was added as a compatibilizer at 0.3 and 0.7 phr (parts per hundred) of PLA/PP resin and dicumyl peroxide (DCP) as an initiator at 0.03 and 0.07 phr. They discovered that a 70:30 blend of 0.3 phr PP\(-\)g\(-\)MAH and 0.03 phr DCP provided the highest yield strength of 27.68 mPa. The preparation of liquid natural rubber (LNR) from the degradation of natural rubber (NR) latex is related to the breaking of the natural rubber (NR) chain via direct scission of the C\(-\)C or C\(-\)C bonds of the polyisoprene backbone. Moreover, LNR with a similar microstructure of NR having a molecular weight below 20,000 g/mol becomes an attractive material for enhancement of further modifications. The graft copolymers consist of one or more side chains structurally distinct from the main polymer chains or backbone. Graft copolymerization is an established technique for modifying core-shell particles, which typically consist of a hard plastic shell phase made of polystyrene or poly(methyl methacrylate) and an elastic rubber core phase made of polybutadiene, poly(butyl acrylate), or polyisoprene. The core phase is capable of cavitating and promoting matrix shear yielding. The shell phase interacts with the matrix via physical or chemical interaction, enabling good particle dispersion in the blends [22; 23]. Graft copolymer synthesis has been performed in solution [24], solid [25], and latex phases [26]; however, latex modification may be the most cost-effective and practical method. The graft copolymer of methyl methacrylate onto LNR (LNR\(-\)g\(-\)MMA), comprising an inner soft polymer sphere (LNR), i.e., the \"core,\" and an outer rigid polymer (PMMA), i.e., the \"shell,\" can be expected to have better impact resistance properties. [PERSON] and [PERSON] [27] reported that the core-shell elastomeric particles maintained their structural integrity while remaining well distributed throughout the PVC matrix after the melt blending process. In this article, we synthesized graft copolymer particles with a core-shell structure made of MMA and a rubbery phase of LNR.