It seems impossible that a start-up cleaning company, mainly engaged in producing chemicals to wash boilers and tea urns, becomes one of the top 500 companies in the world, but Ren Jianxin did it.

And it took him 27 years. Ren, 52, established the enterprise in 1984 and grew it to China National Chemical Corp (ChemChina), with total assets of 248 billion yuan ($39.1 billion). This year, the company made it to the Fortune top 500 enterprises.

Ren, the president of ChemChina, is also widely considered as the "king of mergers", reflecting how he used mergers and acquisitions (M&As) to expand aggressively in the global market.

The Beijing-headquartered company now has more than 140 overseas operations, including facilities in France, Britain, Australia, Norway and Israel.

"It (M&A) is a common way for companies willing to tap into the global market in a globalization era, and it's also an effective way that has proven right for our company's development," Ren said.

The company's recent acquisition of Israel's Makhteshim Agan Group, an off-patent crop and non-crop protection products manufacturer, in October has expanded the State-owned ChemChina's overseas subsidiaries to six. It's also the biggest deal ever between China and Israel.

Ren also attributed his company's success to China's entry into the World Trade Organization (WTO) in 2001.

"The move is also a landmark for our company, which significantly boosts our business in the foreign market," Ren said.

The WTO system provides a fair environment for domestic companies in the foreign markets. "To follow the international practice is extremely important for a Chinese company to operate overseas under the WTO framework," Ren said.

To strengthen its major growth engine in overseas markets, ChemChina has successfully introduced strategic investment from US private equity firm Blackstone Group for a better insight into the global capital market.

The two companies signed agreements in 2007, in which Blackstone invested $600 million for a 20 percent stake in ChemChina's subsidiary China National BlueStar (Group) Co Ltd.

"As we strive to become the world's top three chemical companies, Blackstone's expertise in the capital market amid its worldwide reach will give us a boost," Ren said.

"Overseas expansion is one of our drivers for development; we hope to go further on this," he added.

Moreover, he said even though M&As are mostly profit- and growth-driven, ChemChina also pays attention to local people working at its overseas companies. "They are one of the key assets," Ren said.

For more than 20 years, the company has been organizing summer camps for their global employees' children in China, a tradition aimed at nourishing a culture to show the company's respect to staff.

At ChemChina, "caring for the employees" has become a strong part of the company, Ren said. "That is also what we've learned through our overseas operations."