The security of electronic will notarization systems is increasingly being recognized by countries worldwide. Most existing schemes primarily rely on trusted third parties or blockchain-based time-lock puzzles (TLP) to ensure critical properties. However, these solutions often suffer from trust risks. To address these challenges, we propose a Secure Electronic Notarization Scheme with InterPlanetary File System (IPFS) and Blockchain (SENS-IFSB). Specifically, we introduce block-chain smart contracts as the core controller for document time-release encryption to mitigate security risks from third-party over-reliance. To enhance the flexibility of time-release mechanisms, we implement chained-Elliptic curve cryptography (ECC) encryption that enables adjustable extension of encryption time limits. Furthermore, we leverage the InterPlanetary File System to store time-lock puzzles and encrypted will contents, effectively alleviating blockchain storage pressure. Finally, we formally prove the security of IFSB in SENS-IFSB based on the hardness assumption of the Elliptic Curve Discrete Logarithm Problem (ECDLP). Our analysis demonstrates that the scheme is IND-CPA secure, with experimental results showing 50% improvement in time-release flexibility and 95% reduction in blockchain storage overhead compared to conventional solutions.