PDF
Full
Outline
Ammonia preservation and acid solidification are key steps in natural rubber (NR) processing, but there is still a lack of systematic research on the influence on the structure and properties of NR. In this paper, the same batch of fresh latex was treated with 0%, 0.05%, 0.20% ammonia and two solidification methods (acid solidification, biological solidification) to prepare samples. The effects of ammonia preservation and acid solidification on the structure and properties of NR were comprehensively evaluated from the aspects of molecular structure, composition, intrinsic properties, and the mechanical performance of both unfilled and carbon-black-filled vulcanizates. It was found that ammonia preservation led to a decrease in weight-average molecular weigh, the initial plastic value and Mooney viscosity of the acid-solidified samples, whereas the properties remained largely unaffected in biologically solidified counterparts. The addition of ammonia exerted minimal influence on the mechanical properties of unfilled vulcanizates, but significant effects emerged in carbon-black-filled systems. Acid-solidified samples demonstrated higher fatigue temperature rise, while biologically solidified samples showed decreased tensile stress and tear strength. The solidification mode profoundly impacted the molecular structure, chemical composition, intrinsic properties, and mechanical performance of NR. Compared to biological solidification, acid-solidified rubber exhibits higher nitrogen, free fatty acid content and weight-average molecular weight. Furthermore, acid-solidified samples displayed lower initial plasticity and Mooney viscosity. The solidification method significantly affected the properties of both unfilled and carbon-black-filled vulcanizates. Compared to biological solidification, acid-solidified samples exhibited slower cure rates and higher fatigue temperature rise. The results showed that ammonia preservation of fresh latex and subsequent solidification with acid could affect the important components and intrinsic properties of NR, and had a significant impact on the dynamic properties such as fatigue temperature rise and permanent deformation, especially in carbon-black-filled vulcanizates. However, by comparing with the imported RSS, the preservation of fresh latex with ammonia and the subsequent solidification with acid were not the only reasons causing the performance of domestic NR to be worse than that of imported NR and differences in processing maybe the other causes. This work not only reveals the reason of the performance difference between domestic and imported NR products, but also would provide technical support for optimizing the production management of special rubber park.
PDF
92
53
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
关闭全屏
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
