The use of styrene butadiene rubber (SBR) in tire rubber presents a challenge for the recycling of tire rubber because of its complex degradation behavior compared with that of natural rubber (NR). The effect of the composition of SBR on the degradation of NR was observed by light pyrolysis at variable times at 300 °C. The morphology, sol-gel evolution of the NR/SBR blends and the degradation mechanism was investigated. In addition, the structural evolution of the sol and gel fractions were measured by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The results indicated that the mechanism of degradation between SBR and NR differed significantly at 300 °C. The broken molecular chains present in SBR recombined with themselves or those of NR to form a new crosslinked network. The results also showed that the ratio of NR/SBR in the sol and gel fractions remains almost constant and unrelated to the original ratio of the NR/SBR blends. Following an increase in SBR content, the sol fraction of different NR/SBR blends mainly consisted of the small molecular chains of NR, whereas the gel fraction mostly constituted re-crosslinked SBR molecular chains.

由于与天然橡胶（NR）相比，丁苯橡胶（SBR）的降解行为复杂，因此在轮胎橡胶中使用丁苯橡胶（SBR）对轮胎的回收提出了挑战。通过在300°C的不同时间进行光热解，可以观察到SBR的组成对NR降解的影响。研究了NR / SBR共混物的形态，溶胶-凝胶演变以及降解机理。另外，通过傅立叶变换红外光谱（FTIR）和热重分析（TGA）测量了溶胶和凝胶部分的结构演变。结果表明，在300°C时SBR和NR之间的降解机理存在显着差异。SBR中存在的断裂分子链会与自身或NR分子重组形成新的交联网络。结果还表明，溶胶和凝胶级分中的NR / SBR比例几乎保持恒定，并且与NR / SBR共混物的原始比例无关。随着SBR含量的增加，不同NR / SBR共混物的溶胶级分主要由NR的小分子链组成，而凝胶级分则主要构成了重新交联的SBR分子链。