面对近年来日益突出的环境问题，经济社会的可持续发展成为重要议题。从十八大、十九大相继提出的生态文明建设和绿色低碳发展的现代经济体系，再至 2021 年“双碳“目标的部署和不断推进，我国对企业环保意识及低碳发展观念提升做出新的要求，特别是传统资源型和能耗型污染企业。在此背景下，污染企业不断转变发展思路，调整经济发展结构实现绿色转型升级，而绿色并购这一方式为相关企业实现节能减排、绿色低碳的发展目标提供了新的思路和途径。

本文通过对绿色并购及相关评价方法等文献进行梳理回顾，以协同效应理论、可持续发展理论和利益相关者理论为支持，分析我国污染企业绿色并购转型升级的背景，并分别从年度、行业及股权分布三个维度对2012—2022 年期间我国污染企业绿色并购转型升级现状展开详细分析。为进一步深入了解污染企业绿色并购动因及绩效，选取化工企业奥克股份作为具体研究对象。本文首先介绍奥克股份的基本情况及绿色并购历程，从环境规制和自身发展需要两个角度剖析绿色并购的动因。其次，通过各种方法多维度评价奥克股份公司绿色并购绩效，其中：通过事件研究法评价绿色并购的资本市场反应，采用主成分分析法和熵权法评价奥克股份绿色并购的财务绩效变化，并基于熵权－突变级数法评价并购后的社会绩效。通过上述路径及方法，对污染企业奥克股份绿色并购动因和绩效表现深入研究后综合得出本文研究结论。

综上所述，本文主要有以下两点结论：其一，实施绿色并购是奥克股份内外部环境共同决定的结果，外部动因源于政策约束和激励效应，内部动因则源于改善发展结构和自身业务发展需要，最终的目的是实现企业价值最大化；其二，从绿色并购综合绩效来看，奥克股份的绿色并购是一次绿色转型升级的成功实践，从并购前后公司的财务绩效和市场表现来看，绿色并购对于奥克股份的长短期经济绩效有积极的正向效应，但对社会绩效影响 较小。本文的研究将进一步丰富污染企业绿色并购的研究内容，也将为其他拟实施绿色并购的污染企业提供一定的经验借鉴和决策依据。

In the face of the increasingly prominent environmental issues in recent years, sustainable economic and social development has become an important issue. From the construction of  ecological civilization and the modern economic system of green and low-carbon development proposed successively at the 18th and 19th National Congress to the deployment and continuous promotion of the "dual carbon" goal in 2021, China has made new requirements for the improvement of environmental awareness and low-carbon development concepts of enterprises, especially for traditional resource based and energy consumption based polluting enterprises. In this context, polluting enterprises are constantly changing their development thinking, adjusting their economic development structure to achieve green transformation and upgrading, and green mergers and acquisitions provide new ideas and ways for relevant enterprises to achieve their development goals of energy conservation, emission reduction, and green and low-carbon.

This article reviews the literature on green mergers and acquisitions and related evaluation methods, with the support of synergy theory, sustainable development theory, and stakeholder theory, and analyzes the background of the transformation and upgrading of green mergers and acquisitions of polluting enterprises in China. It also conducts a detailed analysis of the current situation of the transformation and upgrading of green mergers and acquisitions of polluting enterprises in China from 2012 to 2022 from three dimensions, namely, year, industry, and equity distribution. In order to further understand the motivation and performance of green mergers and acquisitions of polluting enterprises, Oxiranchem, a chemical enterprise, was selected as the specific research object. This article first introduces the basic situation of Oxiranchem and the process of green mergers and acquisitions, and analyzes the motivations of green mergers and acquisitions from two perspectives: environmental regulation and self development needs. Secondly, various methods are used to evaluate the green M&A performance of Oxiranchem in multiple dimensions. Among them, the event study method is used to evaluate the capital market response to green M&A, the principal component analysis method and entropy weight method are used to evaluate the financial performance changes of Oxiranchem in green M&A, and the entropy weight catastrophe progression method is used to evaluate the social performance after M&A, as well as to analyze the changes in the company's market value from both the price earnings ratio and the total market value. Through the above paths and methods, in-depth research is conducted on the motivation and performance of the green M&A of the polluting company Oxiranchem, and a comprehensive conclusion is drawn.

To sum up, this article mainly has the following two conclusions: firstly, the implementation of green mergers and acquisitions is the result of the joint determination of the internal and  external environment of Oxiranchem. The external motivation is derived from policy constraints and incentive effects, while the internal motivation is derived from improving the development structure and the needs of one's own business development. The ultimate goal is to achieve maximum enterprise value; Secondly, from the perspective of the comprehensive performance of green mergers and acquisitions, The green merger and acquisition of Oxiranchem is a successful practice of green transformation and upgrading. From the financial and market performance of the company before and after the merger, green mergers and acquisitions have a positive effect on Oxiranchem's long-term and short-term economic performance, but have a relatively small impact on social performance. The research in this article will further enrich the research content of green mergers and acquisitions of polluting enterprises, and provide certain experience and decision-making basis for other polluting enterprises that plan to implement green mergers and acquisitions.