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The results indicate that, compared to acid-coagulated natural rubber, enzyme-assisted microbial coagulated natural rubber exhibits slightly lower levels of volatile matter, impurities, plasticity retention index (PRI), nitrogen content, calcium ions (Ca2+), iron ions (Fe3+), and fatty acid content. Conversely, it demonstrates higher values in ash content, initial plasticity (P0), Mooney viscosity (ML(1+4)), acetone extract, magnesium ions (Mg2+), copper ions (Cu2+), manganese ions (Mn2+), gel content, molecular weight and distribution, and glass transition temperature (Tg). With the increase in the proportion of PR107 and Reyan 72059 fresh latex, the ash content, volatile matter content, fatty acid content, gel content, and dispersion coefficient (PDI) of natural rubber gradually decrease, while the impurity content, PRI, nitrogen content, weight-average molecular weight (Mw), and number-average molecular weight (Mn) gradually increase. Compared to acid-coagulated natural rubber compounds, enzyme-assisted microbial-coagulated natural rubber compounds exhibit higher minimum torque (ML) and maximum torque (MH), but shorter scorch time (t10) and optimum cure time (t90). Furthermore, as the proportion of PR107 and Reyan 72059 fresh latex increases, the ML of the compounds gradually decreases. In pure rubber formulations, enzyme-assisted microbial-coagulated natural rubber vulcanizates demonstrate higher tensile strength, tear strength, modulus at 300%, and Shore A hardness compared to acid-coagulated natural rubber vulcanizates. When the fresh latex ratio of PR107, Reyan 72059, and Reyan 73397 is 1:1:3, the tensile strength and 300% modulus of the natural rubber vulcanizates reach their maximum values. In carbon black formulations, the tensile strength and tear strength of enzyme-assisted microbial-coagulated natural rubber vulcanizates are significantly higher than those of acid-coagulated natural rubber vulcanizates in pure rubber formulations, with the increase exceeding that of other samples.<\/jats:p>","DOI":"10.3390\/polym17162211","type":"journal-article","created":{"date-parts":[[2025,8,13]],"date-time":"2025-08-13T13:30:38Z","timestamp":1755091838000},"page":"2211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["The Effect of the Fresh Latex Ratio on the Composition and Properties of Bio-Coagulated Natural Rubber"],"prefix":"10.3390","volume":"17","author":[{"given":"Jianwei","family":"Li","sequence":"first","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Honghai","family":"Huang","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Ding","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tuo","family":"Dai","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haoran","family":"Geng","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"},{"name":"Center for Smart Materials and Devices, State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tao","family":"Zhao","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liguang","family":"Zhao","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fan","family":"Wu","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongxing","family":"Gui","sequence":"additional","affiliation":[{"name":"Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China"},{"name":"Hainan Provincial Special Natural Rubber Processing Technology Innovation Center, Haikou 571101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1016\/j.resconrec.2018.01.029","article-title":"Sustainability of natural rubber processing can be improved: A case study with crepe rubber manufacturing in Sri Lanka","volume":"133","author":"Dunuwila","year":"2018","journal-title":"Resour. 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