1、假如一種抗氧劑既具有終止活性自在基的功用又具有合成過氧化氫物的功用，也會產(chǎn)生協(xié)同效應(yīng)，這種協(xié)同效應(yīng)稱為自協(xié)同效應(yīng)，某些長效性抗氧劑，因分子中含有兩種不同的功用基團而具有這種特征；
1. If an antioxidant has the function of both terminating activity and synthesizing hydrogen peroxide, it will also produce synergistic effect. This synergistic effect is called self-synergistic effect. Some long-acting antioxidants have this characteristic because they contain two different functional groups in the molecule.
2、臭氧是招致橡膠在大氣中發(fā)作老化的一個重要要素，臭氧比氧更生動，因此它對保送帶特別是不飽和橡膠的侵襲比氧嚴重得多，大氣中的臭氧是由氧分子吸收太陽光中的短波紫外光后，合成出的氧原子重新與氧分子分離而成的，隨著空氣的垂直活動，臭氧被帶到地球外表，臭氧的濃度由高空到空中逐步降低。另外，在紫外光集中的場所、放電場所以及電動機左近，特別是產(chǎn)生電火花的都會產(chǎn)生臭氧，地域不同，臭氧的濃度不同，時節(jié)不同，臭氧的濃度也不同，固然空中左近的臭氧濃度很低，但對橡膠形成的危害卻是不容無視的；
2. Ozone is an important factor that causes rubber aging in the atmosphere. Ozone is more vivid than oxygen. Therefore, it attacked the conveyor belt, especially unsaturated rubber, much more seriously than oxygen. Ozone in the atmosphere is formed by oxygen molecules absorbed short-wave ultraviolet light from the sun, and the synthesized oxygen atoms are separated from oxygen molecules. With the vertical movement of air, ozone is brought to the conveyor belt. Outside the earth, ozone concentration gradually decreases from high altitude to high altitude. In addition, ozone can be produced in the places where ultraviolet light is concentrated, discharge places and motor are near, especially in the center where electric sparks are produced. The concentration of ozone varies from region to region, from time to time, and from time to time. Although the concentration of ozone in the left and near air is very low, the harm to rubber formation can not be ignored.
3、不飽和橡膠極易發(fā)作臭氧化及其臭氧化后的外觀特征，與熱氧老化不同，一是橡膠的臭氧化只在臭氧所接觸的外表層停止，整個臭氧化過程是由表及里的過程，二是橡膠與臭氧反響生成一層雪白色硬膜，在靜態(tài)條件下此膜能阻止臭氧與橡膠深層接觸，但在動態(tài)應(yīng)變條件下或在靜態(tài)拉伸狀態(tài)下當橡膠的伸長或拉伸應(yīng)力超越它的臨界伸長或臨界應(yīng)力時，這層膜會產(chǎn)生龜裂，使臭氧得以與新的橡膠外表接觸，繼續(xù)發(fā)作臭氧化反響并使裂紋增長，另外裂紋呈現(xiàn)后由于基部有應(yīng)力集中，所以更容易加深裂紋進而構(gòu)成裂口，裂紋的方向垂直于應(yīng)力方向，普通在小應(yīng)變下只要少量裂紋呈現(xiàn)，裂紋方向明晰可辨。
3. Unsaturated rubber is very vulnerable to ozonation and its appearance after ozonation. Unlike thermal oxygen aging, the ozonation of rubber stops only in the outer layer of ozone contact. The whole ozonation process is a surface-to-interior process. The reaction between rubber and ozone produces a snow-white hard film, which can prevent ozone from contacting with rubber in deep layer under static conditions, but in dynamic response. When the elongation or tensile stress of rubber exceeds its critical elongation or stress under variable or static tension conditions, the film will crack, which will make ozone contact with the new rubber surface, continue to generate ozonation reaction and crack growth. In addition, the crack will be more prone to deepen the crack and then form the crack direction because of the stress concentration at the base. The direction of crack is perpendicular to the stress direction. In general, the direction of crack can be clearly distinguished if only a few cracks appear under small strain.
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