《关于使用闲置自有资金购买国债逆回购的进展公告》 以上内容为证券之星据公开信息整理，由AI算法生成（网信算备310104345710301240019号），不构成 投资建议。 最新公告列表 截至2026年1月28日收盘，同大股份（300321）报收于40.55元，较前一交易日下跌1.65%，最新总市值 为36.01亿元。该股当日开盘41.4元，最高41.43元，最低40.2元，成交额达4578.26万元，换手率为 1.27%。 同日，公司发布《关于使用闲置自有资金购买国债逆回购的进展公告》。公告显示，山东同大海岛新材 料股份有限公司于2025年12月29日使用闲置自有资金6000万元购买上海证券交易所国债逆回购品种 GC028，每笔3000万元，认购日为2025年12月29日，到期日为2026年1月26日，年化收益率均为 1.645%，收益金额分别为37857.53元和37857.51元。截至公告日，已到期的国债逆回购资金本金和收益 已全部收回。公司已建立内部管理制度，在授权额度内开展投资，独立董事、审计委员会可对资金使用 情况进行监督。 ...

（编辑 丛可心） 证券日报网讯 1月28日，同大股份发布公告称，2025年12月29日，公司动用6000万元闲置自有资金分两 笔购入GC028国债逆回购，年化1.645%，2026年1月26日到期已全额收回本金并合计获收益75715.04 元。 ...

证券代码：300321 证券简称：同大股份 公告编号：2026-002 山东同大海岛新材料股份有限公司 关于使用闲置自有资金购买国债逆回购的进展公告 本公司及董事会全体成员保证信息披露的内容真实、准确、完整，没有虚假记 载、误导性陈述或重大遗漏。 山东同大海岛新材料股份有限公司（以下简称"公司"）于 2025 年 9 月 26 日召开的第六届董事会第十三次会议、第六届监事会第十二次会议审议通过了 二、投资风险分析及风险控制措施 （一）投资风险 1、公司购买的国债逆回购产品受到国内外宏观经济运行、行业周期、汇率 和利率波动等多种因素影响，可能存在一定的投资风险。 2、国债逆回购投资业务在初始成交之时利率即已锁定，收益大小也已确定， 因此在逆回购到期日之间市场利率波动对已发生的交易没有影响。 （二）风险控制措施 1、公司将严格按照《深圳证券交易所上市公司自律监管指引第 2 号——创 业板上市公司规范运作》等有关规定进行国债逆回购。 2、公司已按照相关法律法规要求，建立健全内部管理制度，明确审批和执 行程序，在授权额度内合理开展国债逆回购，保证投资资金的安全和有效增值。 《关于使用闲置自有资金购买国债逆回购和理财产 ...

证券日报网讯 1月14日，同大股份在互动平台回答投资者提问时表示，公司将在定期报告中披露相应期 间的股东人数。 （文章来源：证券日报） ...

Industry Investment Rating - The industry investment rating is "Outperform" and is maintained [2] Core Views - The basic chemical industry index closed at 4569.80 points, up 4.21% from last week, outperforming the CSI 300 index by 2.35% [17] - Among the 25 sub-industries in the chemical sector, all showed gains, with inorganic salts, modified plastics, synthetic resins, and chlor-alkali leading the way with weekly increases of 10.92%, 9.94%, 7.87%, and 7.60% respectively [18][19] - A total of 462 stocks in the chemical sector saw 400 stocks rise (87%) and 57 stocks fall (12%) during the week [21] Summary by Relevant Sections Weekly Chemical Market Overview - The basic chemical industry index rose to 4569.80 points, marking a 4.21% increase compared to the previous week, and outperformed the CSI 300 index by 2.35% [17] - The weekly performance of 25 sub-industries showed no declines, with significant gains in inorganic salts and modified plastics [18][19] Chemical Product Price Trends - Among 380 tracked chemical products, 89 saw price increases while 70 experienced declines [24] - The top ten products with the highest price increases included lithium manganate and lithium battery electrolytes, with increases ranging from 7% to 22% [25] - Conversely, the top ten products with the largest price declines included vitamin VD3 and lithium hexafluorophosphate, with declines ranging from 4% to 13% [26] Key Chemical Sub-Industry Tracking - The polyester filament market remained stable, with average prices for POY, FDY, and DTY showing slight declines [27] - The average industry operating rate for polyester filament was approximately 88.11%, with some facilities undergoing maintenance [28] - The average processing margin for polyester products indicated a slight improvement in profitability compared to the previous week [29] Tire Industry Insights - The operating rates for the full steel tire industry decreased to 55.50%, while the semi-steel tire industry dropped to 63.78% [38] - Export volumes from major tire companies in Southeast Asia showed significant year-on-year declines [39] - The average price of styrene-butadiene rubber increased by approximately 2.45% during the week [40] Refrigerant Market Overview - The R22 refrigerant market remained weak, with prices stabilizing at low levels due to cautious market sentiment [47] - In contrast, the R134a refrigerant market continued to rise, with major producers increasing prices amid tight supply conditions [48]

Market Overview - On January 7, the Shandong state-owned enterprise reform sector fell by 0.13% compared to the previous trading day, with Shida Shenghua leading the decline [1] - The Shanghai Composite Index closed at 4085.77, up 0.05%, while the Shenzhen Component Index closed at 14030.56, up 0.06% [1] Stock Performance - Notable gainers in the Shandong state-owned enterprise reform sector included: - Lixin Chuangtou (600783) with a closing price of 26.94, up 10.00% on a trading volume of 49,900 shares and a transaction value of 134 million [1] - Shandong Molong (002490) closed at 7.70, up 5.77% with a trading volume of 1.1299 million shares and a transaction value of 839 million [1] - Taihe New Materials (002254) closed at 11.71, up 4.46% with a trading volume of 612,500 shares and a transaction value of 707 million [1] Decliners - Key decliners included: - Shida Shenghua (603026) with a closing price of 76.09, down 4.05% and a trading volume of 143,400 shares [2] - Dongjie Intelligent (300486) closed at 18.71, down 3.61% with a trading volume of 210,600 shares [2] - Shandong Zhanggu (002598) closed at 9.15, down 2.76% with a trading volume of 256,500 shares [2] Capital Flow - The Shandong state-owned enterprise reform sector experienced a net outflow of 609 million from institutional investors, while retail investors saw a net inflow of 430 million [2] - The sector's capital flow indicates that institutional investors are withdrawing, while retail investors are increasing their positions [2] Individual Stock Capital Flow - Yanzhou Coal Mining (600188) had a net inflow of 213 million from institutional investors, but a net outflow of 141 million from retail investors [3] - Weichai Heavy Machinery (000880) saw a net inflow of 167 million from institutional investors, with a net outflow of 123 million from retail investors [3] - Lixin Chuangtou (600783) had a significant net inflow of 57.64 million from institutional investors, but retail investors withdrew 29.36 million [3]

证券代码：300321 证券简称：同大股份 公告编号：2026-001 山东同大海岛新材料股份有限公司 关于公司控股股东协议转让公司部分股份获得潍坊市财政局批复 暨控制权拟发生变更的进展公告 本公司及董事会全体成员保证信息披露的内容真实、准确、完整，没有虚假记 载、误导性陈述或重大遗漏。 一、本次权益变动概述 山东同大海岛新材料股份有限公司（以下简称"公司"或"同大股份"）控 股股东潍坊市政金控股集团有限公司(以下简称"潍坊金控")经过公开征集和 综合评审，确定青岛卓岳铭梁新材料科技合伙企业(有限合伙)(以下简称"青岛 卓岳铭梁")为受让方。详见《关于公司控股股东拟通过公开征集受让方的方式 协议转让公司部分股份的提示性公告》（公告编号：2025-004）、《关于公司控 股股东拟通过公开征集受让方的方式协议转让公司部分股份获得潍坊市财政局 批复的公告》（公告编号：2025-006）、《关于公司控股股东拟通过公开征集受 让方的方式协议转让公司部分股份的公告》（公告编号：2025-007）、《关于公 司控股股东拟通过公开征集受让方的方式协议转让公司部分股份的进展公告》 （公告编号：2025-008）、《关于公司控股 ...

山东同大海岛新材料股份有限公司于2025年12月19日使用闲置自有资金8000万元购买上海证券交易所国 债逆回购品种，已到期的本金和收益全部收回。随后于2025年12月29日继续使用6000万元闲置自有资金 购买GC028国债逆回购，期限28天，年化收益率1.645%，资金可滚动使用。公司已建立内部管理制度， 确保资金安全。该事项经第六届董事会第十三次会议和第六届监事会第十二次会议审议通过，不影响公 司主营业务和财务状况。 以上内容为证券之星据公开信息整理，由AI算法生成（网信算备310104345710301240019号），不构成 投资建议。 公司公告汇总：同大股份使用6000万元闲置自有资金购买GC028国债逆回购，期限28天，年化收 益率1.645%。 公司公告汇总：此前于2025年12月19日使用8000万元购买国债逆回购，到期本息已全部收回。 公司公告汇总：购买国债逆回购事项经董事会和监事会审议通过，不影响公司主营业务和财务状 况。 截至2025年12月31日收盘，同大股份（300321）报收于45.28元，较上周的46.33元下跌2.27%。本周， 同大股份12月29日盘中最高价报46.88元。 ...

截至2025年12月30日收盘，同大股份（300321）报收于45.49元，较前一交易日上涨0.4%，最新总市值 为40.4亿元。该股当日开盘45.18元，最高46.41元，最低43.74元，成交额达1.3亿元，换手率为3.23%。 《关于使用闲置自有资金购买国债逆回购的进展公告》 以上内容为证券之星据公开信息整理，由AI算法生成（网信算备310104345710301240019号），不构成 投资建议。 公司近日发布公告称，山东同大海岛新材料股份有限公司于2025年12月19日使用闲置自有资金8000万元 购买上海证券交易所国债逆回购品种，已到期的本金和收益全部收回。随后于2025年12月29日继续使用 6000万元闲置自有资金购买GC028国债逆回购，期限28天，年化收益率1.645%，资金可滚动使用。公司 已建立内部管理制度，确保资金安全。该事项经第六届董事会第十三次会议和第六届监事会第十二次会 议审议通过，不影响公司主营业务和财务状况。 最新公告列表 ...

Summary of Key Points Core Viewpoint - The company, Shandong Tongda Island New Materials Co., Ltd., has engaged in financial activities involving the use of idle funds for government bond reverse repos, indicating a strategy to optimize cash management while maintaining operational stability [1]. Trading Information - On December 29, 2025, the stock price of Tongda shares closed at 45.31 yuan, down by 2.2%, with a turnover rate of 3.01% and a trading volume of 26,700 shares, resulting in a transaction amount of 123 million yuan [1]. - The net outflow of main funds on the same day was 20.34 million yuan, while retail investors saw a net inflow of 12.25 million yuan [2]. Company Announcements - On December 19, 2025, the company utilized 80 million yuan of idle funds to purchase government bond reverse repos, with all principal and earnings fully recovered [1]. - On December 29, 2025, the company continued to invest 60 million yuan of idle funds in GC028 government bond reverse repos, with a term of 28 days and an annualized yield of 1.645% [1][2]. - The investment decision was approved by the sixth board of directors and the sixth supervisory board, and the company has established internal management systems to ensure fund safety without affecting its main business and financial status [1].