Synthetic method of large-particle-size polybutadiene latex

The invention relates to the technical field of high polymer material preparation, and provides a synthesis method of large-particle-size polybutadiene latex. According to the invention, butadiene and a chain transfer agent are added into a reaction solution in batches for polymerization reaction, and polybutadiene obtained in the previous reaction can be used as a seed of the next polymerization reaction, so that multi-step seed polymerization is realized; the method provided by the invention is simple to operate and short in reaction time, and the obtained polybutadiene latex is narrow in particle size distribution; meanwhile, the particle size of the obtained polybutadiene latex can be controlled by controlling the number of times of reaction, and under the condition that the total dosage of butadiene and the chain transfer agent is the same, the larger the number of times of reaction is, the larger the particle size of the obtained polybutadiene latex is. In addition, the solid content of the polybutadien